Blend small amounts of pyoil into a liquid stream processed into a gas cracker

ABSTRACT

A hydrocarbon cracker stream is combined with recycle content pyrolysis oil to form a combined cracker stream and the combined cracker stream is cracked in a cracker furnace to provide an olefin-containing effluent. The r-pyoil can be fed to the cracker feed. More specifically the-pyoil is present in said feedstock in an amount of not more than 20% by weight, based on the total weight of the feedstock.

BACKGROUND

Waste materials, especially non-biodegradable waste materials, cannegatively impact the environment when disposed of in landfills after asingle use. Thus, from an environmental standpoint, it is desirable torecycle as much waste materials as possible. However, recycling wastematerials can be challenging from an economic standpoint.

While some waste materials are relatively easy and inexpensive torecycle, other waste materials require significant and expensiveprocessing in order to be reused. Further, different types of wastematerials often require different types of recycling processes. In manycases, expensive physical sorting of waste materials into relativelypure, single-composition waste volumes is required.

To maximize recycling efficiency, it would be desirable for large-scaleproduction facilities to be able to process feedstocks having recyclecontent originating from a variety of waste materials. Commercialfacilities involved in the production of non-biodegradable productscould benefit greatly from using recycle content feedstocks because thepositive environmental impact of using recycle content feeds couldoffset the negative environmental impact of making non-biodegradableproducts.

A crude pyoil stream has a wide variety of carbon number and molecularweights. Crackers accept feeds typically having a fairly narrow range ofcarbon numbers and the operating conditions are tuned to process suchstandard feeds. The addition of pyoil to such feeds can be problematicin that heavier components in the pyoil can overcrack, foul, or coke thetubes and reduce the yields to olefins and service time. One techniqueis to separate the components of pyoil into fractions that more closelyresemble the standard feedstock. However, separation equipment is costlyand results in problems for use or disposal of the undesirable fraction.It would be desirable to add a pyoil stream to a liquid stream forcracking that leaves open the flexibility to fractionate or notfractionate the pyoil stream prior to cracking.

In addition, the availability of pyoil is in limited quantities, yet thedemand to establish a recycle content in a variety of products continueto grow. It would be desirable to continuously feed a pyoil stream to acracker without the necessity for campaigning the pyoil feed toestablish a recycle content in the products.

SUMMARY

In certain embodiments, the present invention involves the large-scaleproduction of one or more materials having recycle content. The recyclecontent of the products can originate from recycled waste and/or fromrecycle content pyrolysis oil (r-pyoil) produced via pyrolysis ofrecycled waste. In certain embodiments, a pyrolysis unit producingr-pyoil can be co-located with the production facility. In otherembodiments, the r-pyoil can be sourced from a remote pyrolysis unit andtransported to the production facility.

In certain embodiments, the present invention involves a crackerfeedstock composition comprising a recycle content pyrolysis oilcomposition (r-pyoil), wherein the r-pyoil is present in the feedstockin an amount of not more than 20% by weight, based on the total weightof the feedstock.

In certain embodiments, the present invention involves a method formaking one or more olefins, comprising: (a) combining a recycle contentpyrolysis oil composition (r-pyoil) with a non-recycle C5 to C22hydrocarbon stream to form a cracker feed stream, wherein the r-pyoil ispresent in the cracker feed stream in an amount of not more than 20% byweight; and (b) cracking the cracker feed stream in a cracker furnace toprovide an olefin-containing effluent stream.

In certain embodiments, the present invention involves a method formaking olefins, comprising: (a) providing a recycle content pyrolysisoil composition (r-pyoil) having a first impurity content; (b) providinga C5 to C22 hydrocarbon composition; (c) combining the r-pyoil and theC5 to C22 hydrocarbon composition to provide a cracker feedstockcomposition, wherein the cracker feedstock composition has a finalimpurity content at least 50 percent lower than the first impuritycontent; and (d) cracking a cracker feed stream comprising at least aportion of the cracker feedstock in a cracking furnace to provide anolefin-containing effluent stream.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an illustrate of a process for employing a recycle contentpyrolysis oil composition (r-pyoil) to make one or more recycle contentcompositions into r-compositions.

FIG. 2 is an illustration of an exemplary pyrolysis system to at leastpartially convert one or more recycled waste, particularly recycledplastic waste, into various useful r-products.

FIG. 3 is a schematic depiction of pyrolysis treatment throughproduction of olefin containing products.

FIG. 4 is a block flow diagram illustrating steps associated with thecracking furnace and separation zones of a system for producing anr-composition obtained from cracking r-pyoil and non-recycle crackerfeed.

FIG. 5 is a schematic diagram of a cracker furnace suitable forreceiving r-pyoil.

FIG. 6 illustrates a furnace coil configuration having multiple tubes.

FIG. 7 illustrates a variety of feed locations for r-pyoil into acracker furnace.

FIG. 8 illustrates a cracker furnace having a vapor-liquid separator.

FIG. 9 is a block diagram illustrating the treatment of a recyclecontent furnace effluent.

FIG. 10 illustrates a fractionation scheme in a Separation section,including a demethanizer, dethanizer, depropanizer, and thefractionation columns to separate and isolate the main r-compositions,including r-propylene, r-ethylene, r-butylene, and others.

FIG. 11 illustrates the laboratory scale cracking unit design.

FIG. 12 illustrates design features of a plant-based trial feedingr-pyoil to a gas fed cracker furnace.

FIG. 13 is a graph of the boiling point curve of a r-pyoil having 74.86%C8+, 28.17% C15+, 5.91% aromatics, 59.72% paraffins, and 13.73%unidentified components by gas chromatography analysis.

FIG. 14 is a graph of the boiling point curve of a r-pyoil obtained bygas chromatography analysis.

FIG. 15 is a graph of the boiling point curve of a r-pyoil obtained bygas chromatography analysis.

FIG. 16 is a graph of the boiling point curve of a r-pyoil distilled ina lab and obtained by chromatography analysis.

FIG. 17 is a graph of the boiling point curve of r-pyoil distilled inlab with at least 90% boiling by 350° C., 50% boiling between 95° C. and200° C., and at least 10% boiling by 60° C.

FIG. 18 is a graph of the boiling point curve of r-pyoil distilled inlab with at least 90% boiling by 150° C., 50% boiling between 80° C. and145° C., and at least 10% boiling by 60° C.

FIG. 19 is a graph of the boiling point curve of r-pyoil distilled inlab with at least 90% boiling by 350° C., at least 10% by 150° C., and50% boiling between 220° C. and 280° C.

FIG. 20 is a graph of the boiling point curve of r-pyoil distilled inlab with 90% boiling between 250-300° C.

FIG. 21 is a graph of the boiling point curve of r-pyoil distilled inlab with 50% boiling between 60-80° C.

FIG. 22 is a graph of the boiling point curve of r-pyoil distilled inlab with 34.7% aromatic content.

FIG. 23 is a graph of the distillation curve from the r-pyoil use in theplant test

FIG. 24 is a graph of the carbon distribution of the pyoil base on wtpercent in the plant test.

FIG. 25 is a graph of the carbon distribution of the pyoil base on wtpercent in the plant test.

DESCRIPTION

When a numerical sequence is indicated, it is to be understood that eachnumber is modified the same as the first number or last number in thenumerical sequence or in the sentence, e.g. each number is “at least,”or “up to” or “not more than” as the case may be; and each number is inan “or” relationship. For example, “at least 10, 20, 30, 40, 50, 75 wt.% . . . ” means the same as “at least 10 wt. %, or at least 20 wt. %, orat least 30 wt. %, or at least 40 wt. %, or at least 50 wt. %, or atleast 75 wt. %,” etc.; and “not more than 90 wt. %, 85, 70, 60 . . . ”means the same as “not more than 90 wt. %, or not more than 85 wt. %, ornot more than 70 wt. % . . . ” etc.; and “at least 1%, 2%, 3%, 4%, 5%,6%, 7%, 8%, 9% or 10% by weight . . . ” means the same as “at least 1wt. %, or at least 2 wt. %, or at least 3 wt. % . . . ” etc.; and “atleast 5, 10, 15, 20 and/or not more than 99, 95, 90 weight percent”means the same as “at least 5 wt. %, or at least 10 wt. %, or at least15 wt. % or at least 20 wt. % and/or not more than 99 wt. %, or not morethan 95 wt. %, or not more than 90 weight percent . . . ” etc.; or “atleast 500, 600, 750° C. . . . ” means the same as “at least 500° C., orat least 600° C., or at least 750° C. . . . ” etc.

All concentrations or amounts are by weight unless otherwise stated. An“olefin-containing effluent” is the furnace effluent obtained bycracking a cracker feed containing r-pyoil. A “non-recycleolefin-containing effluent” is the furnace effluent obtained by crackinga cracker feed that does not contain r-pyoil. Units on hydrocarbon massflow rate, MF1, and MF2 are in kilo pounds/hr (klb/hr), unless otherwisestated as a molar flow rate.

FIG. 1 is a schematic depiction illustrating an embodiment or incombination with any embodiment mentioned herein of a process foremploying a recycle content pyrolysis oil composition (r-pyoil) to makeone or more recycle content compositions (e.g. ethylene, propylene,butadiene, hydrogen, and/or pyrolysis gasoline): the r-composition.

As shown in FIG. 1, recycled waste can be subjected to pyrolysis inpyrolysis unit 10 to produce a pyrolysis product/effluent comprising arecycle content pyrolysis oil composition (r-pyoil). The r-pyoil can befed to a cracker 20, along with a non-recycle cracker feed (e.g.,propone, ethane, and/or natural gasoline). A recycle content crackedeffluent (r-cracked effluent) can be produced from the cracker and thensubjected to separation in a separation train 30. In an embodiment or incombination with any embodiment mentioned herein or in combination withany of the mentioned embodiments, the r-composition can be separated andrecovered from the r-cracked effluent. The r-propylene stream cancontain predominantly propylene, while the r-ethylene stream can containpredominately ethylene.

As used herein, a furnace includes the convection zone and the radiantzone. A convection zone includes the tubes and/or coils inside theconvection box that can also continue outside the convection boxdownstream of the coil inlet at the entrance to the convection box. Forexample, as shown in FIG. 5, the convection zone 310 includes the coilsand tubes inside the convection box 312 and can optionally extend or beinterconnected with piping 314 outside the convection box 312 andreturning inside the convection box 312. The radiant zone 320 includesradiant coils/tubes 324 and burners 326. The convection zone 310 andradiant zone 320 can be contained in a single unitary box, or inseparate discrete boxes. The convection box 312 does not necessarilyhave to be a separate discrete box. As shown in FIG. 5, the convectionbox 312 is integrated with the firebox 322.

Unless otherwise specified, all component amounts provided herein (e.g.for feeds, feedstocks, streams, compositions, and products) areexpressed on a dry basis.

As used herein, a “r-pyoil” or “r-pyrolysis oil” are interchangeable andmean a composition of matter that is liquid when measured at 25° C. and1 atm, and at least a portion of which is obtained from the pyrolysis ofrecycled waste (e.g., waste plastic or waste stream).

As used herein, “r-ethylene” means a composition comprising: (a)ethylene obtained from cracking of a cracker feed containing r-pyoil, or(b) ethylene having a recycle content value or allotment applied to atleast a portion of the ethylene and “r-propylene” means a compositioncomprising: (a) propylene obtained from cracking of a cracker feedcontaining r-pyoil, or (b) propylene having a recycle content value orallotment applied to at least a portion of the propylene.

Reference to a “r-ethylene molecule” means an ethylene molecule deriveddirectly from the cracking of a cracker feed containing r-pyoil.Reference to a “r-propylene molecule” means a propylene molecule deriveddirectly from a cracker feed containing cracking of r-pyoil.

As used herein, the term “predominantly” means more than 50 percent byweight, unless expressed in mole percent, in which case it means morethan 50 mole %. For example, a predominantly propane stream,composition, feedstock, or product is a stream, composition, feedstock,or product that contains more than 50 weight percent propane, or ifexpressed as mole %, means a product that contains more than 50 mole %propane.

As used herein, the term “recycle content” is used i) as a noun to referto a physical component (e.g., compound, molecule, or atom) originatingfrom r-pyoil or ii) as an adjective modifying a particular composition(e.g., a feedstock or product) at least a portion of which is directlyor indirectly derived from r-pyoil.

As used herein, a composition that is “directly derived” from crackingr-pyoil has at least one physical component that is traceable to anr-composition at least a portion of which is obtained by or with thecracking of r-pyoil, while a composition that is “indirectly derived”from cracking r-pyoil has associated with it a recycle content allotmentand may or may not contain a physical component that is traceable to anr-composition at least a portion of which is obtained by or with thecracking of r-pyoil.

A “recycle content value” is a unit of measure representative of aquantity of material having its origin in r-pyoil. The recycle contentvalue can have its origin in any type of r-pyoil and in any type ofcracker furnace used to crack the r-pyoil.

The particular recycle content value can be determined by a mass balanceapproach or a mass ratio or percentage or any other unit of measure andcan be determined according to any system for tracking, allocating,and/or crediting recycle content among various compositions. A recyclecontent value can be deducted from a recycle content inventory andapplied to a product or composition to attribute recycle content to theproduct or composition. A recycle content value does not have tooriginate from making or cracking r-pyoil unless so stated. In oneembodiment or in combination with any mentioned embodiments, at least aportion of the r-pyoil from which an allotment is obtained is alsocracked in a cracking furnace as described throughout the one or moreembodiments herein.

In one embodiment or in combination with any mentioned embodiments, atleast a portion of the recycle content allotment or allotment or recyclecontent value deposited into a recycle content inventory is obtainedfrom r-pyoil. Desirably, at least 60%, or at least 70%, or at least 80%,or at least 90% or at least 95%, or up to 100% of the:

-   -   a. allotments or    -   b. deposits into a recycle content inventory, or    -   c. recycle content value in a recycle content inventory, or    -   d. recycle content value applied to compositions to make a        recycle content product, intermediate, or article (Recycle PIA)        are obtained from r-pyoil.        A Recycle PIA is a product, intermediate which can include        compounds or compositions containing compounds or polymers,        and/or an article having an associated recycle content value. A        PIA does not have a recycle content value associated with it. As        used herein, the term “recycle content allotment” or “allotment”        means a recycle content value that is transferred from an        originating composition, at least a portion of which recycle        content value is obtained by or with the cracking of r-pyoil, to        a receiving composition (the composition receiving the        allotment) that may or may not have physical component that is        traceable to a composition at least a portion of which is        obtained by or with the cracking of r-pyoil, where the recycle        content value (whether by mass or percentage or any other unit        of measure) is determined according to a standard system for        tracking, allocating, and/or crediting recycle content among        various compositions. A “composition” that receives an allotment        or recycle content value can include a composition of matter,        compound, product, polymer, or article.

A “recycle content allotment” or “allotment” means a recycle contentvalue that is:

-   -   a. transferred from r-pyoil, or recycle waste used to make        r-pyoil (for convenience referred to herein collectively as        “r-pyoil”) to a receiving composition or a Recycle PIA that may        or may not have a physical component that is traceable to the        r-pyoil; or    -   b. deposited into a recycle content inventory, at least a        portion of which originates from r-pyoil.

An allotment can be an allocation or a credit.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the compositionreceiving the recycle content allotment can be a non-recyclecomposition, to thereby convert the non-recycle composition to anr-composition. As used herein, “non-recycle” means a composition none ofwhich was directly or indirectly derived from the cracking of r-pyoil.As used herein, a “non-recycle feed” in the context of a feed to thecracker or furnace means a feed that is not obtained from a waste streamor r-pyoil. Once a non-recycle feed or PIA obtains a recycle contentallotment (e.g. either through a credit or allocation), it becomes arecycle content feed, composition, or Recycle PIA.

As used herein, the term “recycle content allocation” is a type ofrecycle content allotment, where the entity or person supplying thecomposition sells or transfers the composition to the receiving personor entity, and the person entity making the composition has an allotmentat least a portion of which can be associated with the composition soldor transferred by the supplying person or entity to the receiving personor entity. The supplying entity or person can be controlled by the sameperson or entity or a variety of affiliates that are ultimatelycontrolled or owned at least in part by a parent entity (“Family ofEntities”), or they can be from a different Family of Entities.Generally, a recycle content allocation travels with a composition andwith the downstream derivates of the composition. An allocation may bedeposited into a recycle content inventory and withdrawn from therecycle content inventory as an allocation and applied to a compositionto make an r-composition or a Recycle PIA.

The term “recycle content credit” means a recycle content allotment,where the allotment is not restricted to an association withcompositions made from cracking r-pyoil or their downstream derivatives,but rather have the flexibility of being obtained from r-pyoil and (i)applied to compositions or PIA made from processes other than crackingfeedstocks in a furnace, or (ii) applied to downstream derivatives ofcompositions, through one or more intermediate feedstocks, where suchcompositions are made from processes other than cracking feedstocks in afurnace, or (iii) available for sale or transfer to persons or entitiesother than the owner of the allotment, or (iv) available for sale ortransfer by other than the supplier of the composition that istransferred to the receiving entity or person. For example, an allotmentcan be a credit when the allotment is taken from r-pyoil and applied bythe owner of the allotment to a BTX composition, or cuts thereof, madeby said owner or within its Family of Entities, obtained by refining andfractionation of petroleum rather than obtained by cracker effluentproducts; or it can be a credit if the owner of the allotment sells theallotment to a third party to allow the third party to either re-sellthe product or apply the credit to one or more of a third party'scompositions.

A credit can be available for sale or transfer or use, or is sold ortransferred or used, either:

-   -   a. without the sale of a composition, or    -   b. with the sale or transfer of a composition but the allotment        is not associated the sale or transfer of the composition, or    -   c. is deposited into or withdrawn from a recycle content        inventory that does not track the molecules of a recycle content        feedstock to the molecules of the resulting compositions which        were made with the recycle content feedstocks, or which does        have such tracking capability but which did not track the        particular allotment as applied to a composition.

In one embodiment or in combination with any of the mentionedembodiments, an allotment may be deposited into a recycle contentinventory, and a credit or allocation may be withdrawn from theinventory and applied to a composition. This would be the case where anallotment is created from a r-pyoil and deposited into a recycle contentinventory, and deducting a recycle content value from the recyclecontent inventory and applying it to a composition to make anr-composition that either has no portion originating from the productsof a cracker furnace, or does have a portion originating from theproducts of a cracker furnace but such products making up the portion ofthe composition were not obtained by cracking r-pyoil. In this system,one need not trace the source of a reactant back to the cracking r-pyoilolefin-containing effluent olefin-containing effluent olefin-containingeffluent or back to any atoms contained in r-pyoil olefin-containingeffluent olefin-containing effluent olefin-containing effluent, butrather can use any reactant made by any process and have associated withsuch reactant a recycle content allotment.

In one embodiment or in combination with any mentioned embodiments, acomposition receiving an allotment is used as a feedstock to makedownstream derivatives of the composition, and such composition is aproduct of cracking a cracker feedstock in a cracker furnace. In oneembodiment or in combination with any mentioned embodiments, there isprovided a process in which:

-   -   a. a r-pyoil is obtained,    -   b. a recycle content value (or allotment) is obtained from the        r-pyoil and        -   i. deposited into a recycle content inventory, and an            allotment (or credit) is withdrawn from the recycle content            inventory and applied to any composition to obtain a            r-composition, or        -   ii. applied directly to any composition, without depositing            into a recycle content inventory, to obtain an            r-composition; and    -   c. at least a portion of the r-pyoil is cracked in a cracker        furnace, optionally according to any of the designs or processes        described herein; and    -   d. optionally at least a portion of the composition in step b.        originates from a cracking a cracker feedstock in a cracker        furnace, optionally the composition having been obtained by any        of the feedstocks, including r-pyoil, and methods described        herein.

The steps b. and c. do not have to occur simultaneously. In oneembodiment or in combination with any mentioned embodiments, they occurwithin a year of each other, or within six (6) months of each other, orwithin three (3) months of each other, or within one (1) month of eachother, or within two (2) weeks of each other, or within one (1) week ofeach other, or within three (3) days of each other. The process allowsfor a time lapse between the time an entity or person receiving ther-pyoil and creating the allotment (which can occur upon receipt orownership of the r-pyoil or deposit into inventory) and the actualprocessing of the r-pyoil in a cracker furnace.

As used herein, “recycle content inventory” and “inventory” mean a groupor collection of allotments (allocations or credits) from which depositsand deductions of allotments in any units can be tracked. The inventorycan be in any form (electronic or paper), using any or multiple softwareprograms, or using a variety of modules or applications that together asa whole tracks the deposits and deductions. Desirably, the total amountof recycle content withdrawn (or applied to compositions) does notexceed the total amount of recycle content allotments on deposit in therecycle content inventory (from any source, not only from cracking ofr-pyoil). However, if a deficit of recycle content value is realized,the recycle content inventory is rebalanced to achieve a zero orpositive recycle content value available. The timing for rebalancing canbe either determined and managed in accordance with the rules of aparticular system of accreditation adopted by the olefin-containingeffluent manufacturer or by one among its Family of Entities, oralternatively, is rebalanced within one (1) year, or within six (6)months, or within three (3) months, or within one (1) month of realizingthe deficit. The timing for depositing an allotment into the recyclecontent inventory, applying an allotment (or credit) to a composition tomake a r-composition, and cracking r-pyoil, need not be simultaneous orin any particular order. In one embodiment or in combination with anymentioned embodiments, the step of cracking a particular volume ofr-pyoil occurs after the recycle content value or allotment from thatvolume of r-pyoil is deposited into a recycle content inventory.Further, the allotments or recycle content values withdrawn from therecycle content inventory need not be traceable to r-pyoil or crackingr-pyoil, but rather can be obtained from any waste recycle stream, andfrom any method of processing the recycle waste stream. Desirably, atleast a portion of the recycle content value in the recycle contentinventory is obtained from r-pyoil, and optionally at least a portion ofr-pyoil, are processed in the one or more cracking processes asdescribed herein, optionally within a year of each other and optionallyat least a portion of the volume of r-pyoil from which a recycle contentvalue is deposited into the recycle content inventory is also processedby any or more of the cracking processes described herein.

The determination of whether the r-composition is derived directly orindirectly from cracking r-pyoil is not on the basis of whetherintermediate steps or entities do or do not exist in the supply chain,but rather whether at least a portion of the r-composition that is fedto the reactor for making an end product can be traced to r-compositionmade from the cracking of r-pyoil.

As noted above, the end product is considered to be directly derivedfrom cracking r-pyoil if at least a portion of the atoms or molecules inreactant feedstock used to make the product can be traced back,optionally through one or more intermediate steps or entities, to atleast a portion of the atoms or molecules that make up an r-compositionproduced during the cracking of r-pyoil fed to the cracking furnace. Anynumber of intermediaries and intermediate derivates can be made beforethe r-composition is made. The r-composition manufacturer can, typicallyafter refining and/or purification and compression to produce thedesired grade of the particular r-composition, sell such r-compositionto an intermediary entity who then sells the r-composition, or one ormore derivatives thereof, to another intermediary for making anintermediate product or directly to the product manufacturer. Any numberof intermediaries and intermediate derivates can be made before thefinal product is made. The actual r-composition volume, whethercondensed as a liquid, supercritical, or stored as a gas, can remain atthe facility where it is made, or can be shipped to a differentlocation, or held at an off-site storage facility before utilized by theintermediary or product manufacturer. For purposes of tracing, oncer-composition made by cracking r-pyoil is mixed with another volume ofthe composition (e.g. r-ethylene mixed with non-recycle ethylene), forexample in a storage tank, salt dome, or cavern, then the entire tank,dome, or cavern at that point becomes a r-composition source, and forpurposes of tracing, withdrawal from such storage facility iswithdrawing from an r-composition source until such time as when theentire volume or inventory of the storage facility is turned over orwithdrawn and/or replaced with non-recycle compositions after ther-composition feed to the tank stops.

An r-composition is considered to be indirectly derived from thecracking of r-pyoil if it has associated with it a recycle contentallotment and may or may not contain a physical component that istraceable to an r-composition at least a portion of which is obtained byor with the cracking of r-pyoil. For example, the (i) manufacturer ofthe product can operate within a legal framework, or an associationframework, or an industry recognized framework for making a claim to arecycle content through, for example, a system of credits transferred tothe product manufacturer regardless of where or from whom ther-composition, or derivatives thereof, or reactant feedstocks to makethe product, is purchased or transferred, or (ii) a supplier of ther-composition or a derivate thereof (“supplier”) operates within anallotment framework that allows for associating a recycle content valueto a portion or all of an olefin-containing effluent or a compoundwithin an olefin-containing effluent or derivate thereof and to transferthe allotment to the manufacturer of the product or any intermediary whoobtains a supply of one or more compounds in an olefin-containingeffluent, or its derivatives, from the supplier. The transfer can occurby virtue of the supplier transferring an r-compound to the manufacturerof the product or intermediary, or by transferring the allotment (e.g.credit) without associating such allotment to the compound transferred.In this system, one need not trace the source of an olefin volume fromcracking r-pyoil, but rather can use any olefin volume made by anyprocess and have associated with such olefin volume a recycle contentallotment.

Examples of where the r-composition is r-olefin (e.g. r-ethylene orr-propylene) and the product is an olefin-derived petrochemical (e.g.reaction product of the r-olefin or blend with the r-olefin) that isdirectly or indirectly derived from the r-olefin obtained from r-pyoilinclude:

a cracker facility in which the r-olefin made at the facility can be influid communication, continuously or intermittently, with anolefin-derived petrochemical formation facility (which can be to astorage vessel at the olefin-derived petrochemical facility or directlyto the olefin-derived petrochemical formation reactor) throughinterconnected pipes, optionally through one or more storage vessels andvalves or interlocks, and the r-olefin feedstock is drawn through theinterconnected piping:

from the cracker facility while r-olefin is being made or thereafterwithin the time for the r-olefin to transport through the piping to theolefin-derived petrochemical formation facility or

from the one or more storage tanks at any time provided that at leastone of the storage tanks was fed with r-olefin, and continue for so longas the entire volume of the one or more storage tanks is replaced with afeed that does not contain r-olefin; or

transporting olefin from a storage vessel, dome, or facility, or in anisotainer via truck or rail or ship or a means other than piping, thatcontains or has been fed with r-olefin until such time as the entirevolume of the vessel, dome or facility has been replaced with an olefinfeed that does not contain r-olefin; or

the manufacturer of the olefin-derived petrochemical certifies,represents to its customers or the public, or advertises that itsolefin-derived petrochemical contains recycle content or is obtainedfrom feedstock containing or obtained from recycle content, where suchrecycle content claim is based in whole or in part on obtainingr-olefin; or

the manufacturer of the olefin-derived petrochemical has acquired:

an olefin volume made from r-pyoil under a certification,representation, or as advertised, or

has transferred credits with the supply of olefin to the manufacturer ofthe olefin-derived petrochemical sufficient to allow the manufacturer ofthe olefin-derived petrochemical to satisfy the certificationrequirements or to make its representations or advertisements, or anolefin that has an associated recycle content value where such recyclecontent value was obtained, through one or more intermediary independententities, from r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the recyclecontent can be directly or indirectly derived from cracking r-pyoil,where at least a portion of the r-pyoil is obtained from the pyrolysisof recycled waste (e.g., waste plastic or waste stream).

In one embodiment or in combination with any mentioned embodiments,there is provided a variety of methods for apportioning the recyclecontent among the various olefin-containing effluent volumes, orcompounds thereof, made by any one entity or a combination of entitiesamong the Family of Entities olefin-containing effluent. For example,the cracker furnace owner or operator olefin-containing effluent, or anyamong its Family of Entities, or a Site, can:

-   -   a. adopt a symmetric distribution of recycle content values        among at least two compounds within the olefin-containing        effluent or among RIA it makes based on the same fractional        percentage of recycle content in one or more feedstocks or based        on the amount of allotment received. For example, if 5 wt. % of        the entire cracker feedstock to a furnace is r-pyoil, then one        or more of the compounds in the olefin-containing effluent may        contain 5 wt. % recycle content value, or one or more compounds        can contain 5 wt. % recycle content value less any yield losses,        or one or more of the PIA can contain a 5% recycle content        value. In this case, the amount of recycle content in the        compounds is proportional to all the other products receiving        the recycle content value; or    -   b. adopt an asymmetric distribution of recycle content values        among the compounds in the olefin-containing effluent or among        its PIA. In this case, the recycle content value associated with        a compound or RIA on a can exceed the recycle content value        associated with other compounds or RIA. For example, one volume        or batch of olefin-containing effluent can receive a greater        amount of recycle content value that other batches or volume of        olefin-containing effluent, or one or a combination of compounds        among the olefin-containing effluent to receive a        disproportionately higher amount of recycle content value        relative to the other compounds in the olefin-containing        effluent or other PIA, some of which may receive no recycle        content value. One volume of olefin-containing effluent or PIA        can contain 20% recycle content by mass, and another volume or        RIA can contain zero 0% recycle content, even though both        volumes may be compositionally the same and continuously        produced, provided that the amount of recycle content value        withdrawn from a recycle content inventory and applied to the        olefin-containing effluent does not exceed the amount of recycle        content value deposited into the recycle content inventory, or        if a deficit is realized, the overdraft is rebalanced to zero or        a positive credit available status as described above, or if no        recycle content inventory exists, then provided that total        amount of recycle content value associated with any one more        compounds in the olefin-containing effluent does not exceed the        allotment obtained from the r-pyoil or it is exceeded, is then        rebalanced. In the asymmetric distribution of recycle content, a        manufacturer can tailor the recycle content to volumes of        olefin-containing effluent or to the compounds of interest in        the olefin-containing effluent or PIA that are sold as needed        among customers, thereby providing flexibility among customers        some of whom may need more recycle content than others in an        r-compound or Recycle PIA.

In an embodiment or in combination with any embodiment mentioned herein,both the symmetric distribution and the asymmetric distribution ofrecycle content can be proportional on a Site wide basis, or on amulti-Site basis. In one embodiment or in combination with any of thementioned embodiments, the recycle content obtained from r-pyoil can bewithin a Site, and recycle content values from the r-pyoil can beapplied to one or more olefin-containing effluent volumes or one or morecompounds in a volume of olefin-containing effluent or to one or morePIA made at the same Site from compounds in an olefin-containingeffluent. The recycle content values can be applied symmetrically orasymmetrically to one or more different olefin-containing effluentvolumes or one or more compounds within an olefin-containing effluent orPIA made at the Site.

In one embodiment or in combination with any of the mentionedembodiments, the recycle content input or creation (recycle contentfeedstock or allotments) can be to or at a first Site, and recyclecontent values from said inputs are transferred to a second Site andapplied to one or more compositions made at a second Site. The recyclecontent values can be applied symmetrically or asymmetrically to thecompositions at the second Site. A recycle content value that isdirectly or indirectly “derived from cracking r-pyoil”, or a recyclecontent value that is “obtained from cracking r-pyoil” or originating incracking r-pyoil does not imply the timing of when the recycle contentvalue or allotment is taken, captured, deposited into a recycle contentinventory, or transferred. The timing of depositing the allotment orrecycle content value into a recycle content inventory, or realizing,recognizing, capturing, or transferring it, is flexible and can occur asearly as receipt of r-pyoil onto the site within a Family of Entities,possessing it, or bringing the r-pyoil into inventory by the entity orperson, or within the Family of Entities, owning or operating thecracker facility. Thus, an allotment or recycle content value on avolume of r-pyoil can be obtained, captured, deposited into a recyclecontent inventory, or transferred to a product without having yet fedthat volume to cracker furnace and cracked. The allotment can also beobtained during feeding r-pyoil to a cracker, during cracking, or whenan r-composition is made. An allotment taken when r-pyoil is owned,possessed, or received and deposited into a recycle content inventory isan allotment that is associated with, obtained from, or originates fromcracking r-pyoil even though, at the time of taking or depositing theallotment, the r-pyoil has not yet been cracked, provided that ther-pyoil is at some future point in time cracked.

In an embodiment, the r-composition, or downstream reaction productsthereof, or Recycle PIA, has associated with it, or contains, or islabelled, advertised, or certified as containing recycle content in anamount of at least 0.01 wt. %, or at least 0.05 wt. %, or at least 0.1wt. %, or at least 0.5 wt. %, or at least 0.75 wt. %, or at least 1 wt.%, or at least 1.25 wt. %, or at least 1.5 wt. %, or at least 1.75 wt.%, or at least 2 wt. %, or at least 2.25 wt. %, or at least 2.5 wt. %,or at least 2.75 wt. %, or at least 3 wt. %, or at least 3.5 wt. %, orat least 4 wt. %, or at least 4.5 wt. %, or at least 5 wt. %, or atleast 6 wt. %, or at least 7 wt. %, or at least 10 wt. %, or at least 15wt. %, or at least 20 wt. %, or at least 25 wt. %, or at least 30 wt. %,or at least 35 wt. %, or at least 40 wt. %, or at least 45 wt. %, or atleast 50 wt. %, or at least 55 wt. %, or at least 60 wt. %, or at least65 wt. % and/or the amount can be up to 100 wt. %, or up to 95 wt. %, orup to 90 wt. %, or up to 80 wt. %, or up to 70 wt. %, or up to 60 wt. %,or up to 50 wt. %, or up to 40 wt. %, or up to 30 wt. %, or up to 25 wt.%, or up to 22 wt. %, or up to 20 wt. %, or up to 18 wt. %, or up to 16wt. %, or up to 15 wt. %, or up to 14 wt. %, or up to 13 wt. %, or up to11 wt. %, or up to 10 wt. %, or up to 8 wt. %, or up to 6 wt. %, or upto 5 wt. %, or up to 4 wt. %, or up to 3 wt. %, or up to 2 wt. %, or upto 1 wt. %, or up to 0.9 wt. %, or up to 0.8 wt. %, or up to 0.7 wt. %.The recycle content value associated with the r-composition, r-compoundsor downstream reaction products thereof can be associated by applying anallotment (credit or allocation) to any composition, compound, PIA madeor sold. The allotment can be contained in an inventory of allotmentscreated, maintained or operated by or for the Recycle PIA orr-composition manufacturer. The allotment can be obtained from anysource along any manufacturing chain of products provided that itsorigin is in cracking a feedstock containing r-pyoil.

In one embodiment or in combination with any mentioned embodiments, theRecycle PIA manufacturer can make a Recycle PIA, or process a reactantto make a Recycle PIA by obtaining, from any source, a reactant (e.g.any of the compounds of an olefin-containing cracker effluent) from asupplier (e.g. a cracker manufacturer or one among its Family ofEntities), whether or not such reactant has any recycle content, andeither:

-   -   i. from the same supplier of the reactant, also obtain a recycle        content allotment applied to the reactant, or    -   ii. from any person or entity, obtaining a recycle content        allotment without a supply of a reactant from said person or        entity transferring said recycle content allotment.

The allotment in (i) is obtained from a reactant supplier who alsosupplies a reactant to the Recycle PIA manufacturer or within its Familyof Entities. The circumstance described in (i) allows a Recycle PIAmanufacturer to obtain a supply of a reactant that is a non-recyclecontent reactant yet obtain a recycle content allotment from thereactant supplier. In one embodiment or in combination with anymentioned embodiments, the reactant supplier transfers a recycle contentallotment to the Recycle PIA manufacturer and a supply of a reactant(e.g. propylene, ethylene, butylene, etc.) to the Recycle PIAmanufacturer, where the recycle content allotment is not associated withthe reactant supplied, or even not associated with any reactant made bythe reactant supplier. The recycle content allotment does not have to betied to the reactant supplied or tied to an amount of recycle content ina reactant used to make Recycle PIA, olefin-containing effluentolefin-containing effluent This allows flexibility among the reactantsupplier and Recycle PIA manufacturer to apportion a recycle contentamong the variety of products they each make. In each of these cases,however, the recycle content allotment is associated with crackingr-pyoil.

In one embodiment or in combination with any mentioned embodiments, thereactant supplier transfers a recycle content allotment to the RecyclePIA manufacturer and a supply of reactant to the Recycle PIAmanufacturer, where the recycle content allotment is associated with thereactant. The transfer of the allotment can occur merely by virtue ofsupplying the reactant having an associated recycle content. Optionally,the reactant being supplied is an r-compound separated from anolefin-containing effluent made by cracking r-pyoil and at least aportion of the recycle content allotment is associated with ther-compound (or r-reactant). The recycle content allotment transferred tothe Recycle PIA manufacturer can be up front with the reactant supplied,optionally in installments, or with each reactant installment, orapportioned as desired among the parties.

The allotment in (ii) is obtained by the Recycle PIA manufacturer (orits Family of Entities) from any person or entity without obtaining asupply of reactant from the person or entity. The person or entity canbe a reactant manufacturer that does not supply reactant to the RecyclePIA manufacturer or its Family of Entities, or the person or entity canbe a manufacturer that does not make the reactant. In either case, thecircumstances of (ii) allows a Recycle PIA manufacturer to obtain arecycle content allotment without having to purchase any reactant fromthe entity or person supplying the recycle content allotment. Forexample, the person or entity may transfer a recycle content allotmentthrough a buy/sell model or contract to the Recycle PIA manufacturer orits Family of Entities without requiring purchase or sale of anallotment (e.g. as a product swap of products that are not a reactant),or the person or entity may outright sell the allotment to the RecyclePIA manufacturer or one among its Family of Entities. Alternatively, theperson or entity may transfer a product, other than a reactant, alongwith its associated recycle content allotment to the Recycle PIAmanufacturer. This can be attractive to a Recycle PIA manufacturer thathas a diversified business making a variety of PIA other than thoserequiring made from the supplied reactant.

The allotment can be deposited into a recycle content inventory (e.g. aninventory of allotments). In one embodiment or in combination with anymentioned embodiments, the allotment is created by the manufacturer ofthe olefin-containing effluent olefin-containing effluentolefin-containing effluent. The manufacturer can also make a PIA,whether or not a recycle content is applied to the PIA and whether ornot recycle content, if applied to the PIA, is drawn from the recyclecontent inventory. For example, the olefin-containing effluentolefin-containing effluent manufacturer of the olefin-containingeffluent may:

-   -   a. deposit the allotment into an inventory and merely store it;        or    -   b. olefin-containing effluent olefin-containing effluent deposit        the allotment into an inventory and apply allotments from the        inventory to a compound or compounds within the        olefin-containing effluent or to any PIA made by the        manufacturer, or    -   c. sell or transfer the allotment to a third party from the        recycle content inventory into which at least one allotment,        obtained as noted above, was deposited.

If desired, any recycle content allotment can be deducted in any amountand applied to a PIA to make a Recycle PIA or applied to a non-recycleolefin-containing effluent to make an olefin-containing effluent. Forexample, allotments can be generated having a variety of sources forcreating the allotments. Some recycle content allotments (credits) canhave their origin in methanolysis of recycle waste, or from gasificationof other types of recycle waste, or from mechanical recycling of wasteplastic or metal recycling, or from any other chemical or mechanicalrecycling technology. The recycle content inventory may or may not trackthe origin or basis of obtaining a recycle content value, or theinventory may not allow one to associate the origin or basis of anallotment to the allotment applied to r-composition. It is sufficientthat an allotment is deducted from a the recycle content inventory andapplied to a PIA or a non-recycle olefin-containing effluent regardlessof the source or origin of the allotment, provided that a recyclecontent allotment derived from r-pyoil is present in the recycle contentinventory at the time of withdrawal, or a recycle content allotment isobtained by the Recycle PIA manufacturer as specified in step (i) orstep (ii), whether or not that recycle content allotment is actuallydeposited into the recycle content inventory.

In one embodiment or in combination with any mentioned embodiments, therecycle content allotment obtained in step (i) or (ii) is deposited intoan inventory of allotments. In one embodiment or in combination with anymentioned embodiments, the recycle content allotment deducted from therecycle content inventory and applied to PIA or a non-recycleolefin-containing effluent (or any compounds therein) originates fromr-pyoil.

As used throughout, the recycle content inventory can be owned by theowner of a cracker furnace that processes r-pyoil or one among itsFamily of Entities, olefin-containing effluent or by the Recycle PIAmanufacturer, or operated by either of them, or owned or operated byneither but at least in part for the benefit of either of them, orlicensed by or to either of them. Also, cracker olefin-containingeffluent manufacturer or the Recycle PIA manufacturer may also includeeither of their Family of Entities. For example, while either of themmay not own or operate the inventory, one among its Family of Entitiesmay own such a platform, or license it from an independent vendor, oroperate it for either of them. Alternatively, an independent entity mayown and/or operate the inventory and for a service fee operate and/ormanage at least a portion of the inventory for either of them.

In one embodiment or in combination with any mentioned embodiments, theRecycle PIA manufacturer obtains a supply of reactant from a supplier,and also obtains an allotment from the supplier, where such allotment isderived from r-pyoil, and optionally the allotment is associated withthe reactant supplied by the supplier. In one embodiment or incombination with any mentioned embodiments, at least a portion of theallotment obtained by the Recycle PIA manufacturer is either:

-   -   a. applied to PIA made by the supply of the reactant;    -   b. applied to PIA made by the same type of reactant but not made        by the volume of reactant supplied, such as would be the case        where PIA made with the same type of reactant is already made        and stored in inventory or future made PIA; or    -   c. deposited into an inventory from which is deducted an        allotment that is applied to PIA made by other than the type of        reactant supplied, or    -   d. deposited into an inventory and stored.

It is not necessary in all embodiments that r-reactant is used to makeRecycle PIA or that the Recycle PIA was obtained from a recycle contentallotment associated with a reactant. Further, it is not necessary thatan allotment be applied to the feedstock for making the Recycle PIA towhich recycle content is applied. Rather, as noted above, the allotment,even if associated with a reactant when the reactant is obtained, can bedeposited into an electronic inventory. In one embodiment or incombination with any mentioned embodiments, however, reactant associatedwith the allotment is used to make the Recycle PIA. In one embodiment orin combination with any mentioned embodiments, the Recycle PIA isobtained from a recycle content allotment associated with an r-reactant,or r-pyoil, or with cracking r-pyoil. In one embodiment or incombination with any mentioned embodiments,

In one embodiment or in combination with any mentioned embodiments, theolefin-containing effluent olefin-containing effluent olefin-containingeffluent manufacturer generates an allotment from r-pyoil, and either:

-   -   a. Applies the allotment to any PIA made directly or indirectly        (e.g. through a reaction scheme of several intermediates) from        cracking r-pyoil olefin-containing effluent olefin-containing        effluent; or    -   b. Applies the allotment to any PIA not made directly or        indirectly from cracking r-pyoil olefin-containing effluent        olefin-containing effluent, such as would be the case where the        PIA is already made and stored in inventory or future made PIA;        or    -   c. deposited into an inventory from which is deducted any        allotment that is applied to PIA; and the deposited allotment        either is or is not associated with the particular allotment        applied to the PIA; or    -   d. is deposited into an inventory and stored for use at a later        time.

There is now also be provided a package or a combination of a RecyclePIA and a recycle content identifier associated with Recycle PIA, wherethe identifier is or contains a representation that the Recycle PIAcontains or is sourced from or associated with a recycle content. Thepackage can be any suitable package for containing a polymer and/orarticle, such as a plastic or metal drum, railroad car, isotainer,totes, polytote, bale, IBC totes, bottles, compressed bales, jerricans,and polybags, spools, roving, winding, or cardboard packaging. Theidentifier can be a certificate document, a product specificationstating the recycle content, a label, a logo or certification mark froma certification agency representing that the article or package containscontents or the Recycle PIA contains, or is made from sources orassociated with recycle content, or it can be electronic statements bythe Recycle PIA manufacturer that accompany a purchase order or theproduct, or posted on a website as a statement, representation, or alogo representing that the Recycle PIA contains or is made from sourcesthat are associated with or contain recycle content, or it can be anadvertisement transmitted electronically, by or in a website, by email,or by television, or through a tradeshow, in each case that isassociated with Recycle PIA. The identifier need not state or representthat the recycle content is derived from r-pyoil. Rather, the identifiercan merely convey or communicate that the Recycle PIA has or is sourcedfrom a recycle content, regardless of the source. However, the RecyclePIA has a recycle content allotment that, at least in part, associatedwith r-pyoil.

In one embodiment or in combination with any mentioned embodiments, onemay communicate recycle content information about the Recycle PIA to athird party where such recycle content information is based on orderived from at least a portion of the allocation or credit. The thirdparty may be a customer of the olefin-containing effluentolefin-containing effluent manufacturer or of the Recycle PIAmanufacturer or may be any other person or entity or governmentalorganization other than the entity owning the either of them. Thecommunication may electronic, by document, by advertisement, or anyother means of communication.

In one embodiment or in combination with any mentioned embodiments,there is provided a system or package comprising:

-   -   a. Recycle PIA, and    -   b. an identifier such as a credit, label or certification        associated with said PIA, where the identifier is a        representation that the PIA has, or is sourced from, a recycle        content (which does not have to identify the source of the        recycle content or allotment)        provided that the Recycle PIA made thereby has an allotment, or        is made from a reactant, at least in part associated with        r-pyoil.

The system can be a physical combination, such as package having atleast Recycle PIA as its contents and the package has a label, such as alogo, that the contents such as the Recycle PIA has or is sourced from arecycle content. Alternatively, the label or certification can be issuedto a third party or customer as part of a standard operating procedureof an entity whenever it transfers or sells Recycle PIA having orsourced from recycle content. The identifier does not have to bephysically on the Recycle PIA or on a package and does not have to be onany physical document that accompanies or is associated with the RecyclePIA or package. For example, the identifier can be an electronicdocument, certification, or accreditation logo associated with the saleof the Recycle PIA to a customer. The identifier itself need only conveyor communicate that the Recycle PIA has or is sourced from a recyclecontent, regardless of the source. In one embodiment or in combinationwith any mentioned embodiments, articles made from the Recycle PIA mayhave the identifier, such as a stamp or logo embedded or adhered to thearticle or package. In one embodiment or in combination with anymentioned embodiments, the identifier is an electronic recycle contentcredit from any source. In one embodiment or in combination with anymentioned embodiments, the identifier is an electronic recycle contentcredit having its origin in r-pyoil.

The Recycle PIA is made from a reactant, whether or not the reactant isa recycle content reactant. Once a PIA is made, it can be designated ashaving recycle content based on and derived from at least a portion ofthe allotment. The allotment can be withdrawn or deducted from a recyclecontent inventory. The amount of the deduction and/or applied to the PIAcan correspond to any of the method e.g. a mass balance approach.

In an embodiment, a Recycle PIA can be made by having a recycle contentinventory, and reacting a reactant in a synthetic process to make PIA,withdrawing an allotment from the recycle content inventory having arecycle content value, and applying the recycle content value to the PIAto thereby obtain a Recycle PIA. The amount of allotment deducted frominventory is flexible and will depend on the amount of recycle contentapplied to the PIA. It should be at least sufficient to correspond withat least a portion if not the entire amount of recycle content appliedto the PIA. The recycle content allotment applied to the PIA does nothave to have its origin in r-pyoil, and instead can have its origin inany other method of generating allotments from recycle waste, such asthrough methanolysis or gasification of recycle waste, provided that therecycle content inventory also contains an allotment or has an allotmentdeposit having its origin in r-pyoil. In one embodiment or incombination with any mentioned embodiments, however, the recycle contentallotment applied to the PIA is an allotment obtained from r-pyoil.

The following are examples of applying a recycle content to PIA or tonon-recycle olefin-containing effluents or compounds therein:

-   -   1. A PIA manufacturer applies at least a portion of an allotment        to a PIA to obtain Recycle PIA where the allotment is associated        with r-pyoil and the reactant used to make the PIA did not        contain any recycle content; or    -   2. A PIA manufacturer applies at least a portion of an allotment        to PIA to obtain Recycle PIA, where the allotment is obtained        from a recycle content reactant, whether or not such reactant        volume is used to make the Recycle PIA; or    -   3. A PIA manufacturer applies at least a portion of an allotment        to a PIA to make Recycle PIA where the allotment is obtained        from r-pyoil, and:        -   a. all of the recycle content in the r-pyoil is applied to            determine the amount of recycle content in the Recycle PIA,            or        -   b. only a portion of the recycle content in the r-pyoil            feedstock is applied to determine the amount of recycle            content in the Recycle PIA, the remainder stored in a            recycle content inventory for future use or for application            to other PIA, or to increase the recycle content on an            existing Recycle PIA, or a combination thereof, or        -   c. none of the recycle content in the r-pyoil feedstock is            applied to the PIA and instead is stored in an inventory,            and a recycle content from any source or origin is deducted            from the inventory and applied to PIA to make Recycle PIA;            or    -   4. A Recycle PIA manufacturer applies at least a portion of an        allotment to a reactant used to make a PIA to thereby obtain a        Recycle PIA, where the allotment was obtained with the transfer        or purchase of the same reactant used to make the PIA and the        allotment is associated with the recycle content in a reactant;        or    -   5. A Recycle PIA manufacturer applies at least a portion of an        allotment to a reactant used to make a PIA to thereby obtain a        Recycle PIA, where the allotment was obtained with the transfer        or purchase of the same reactant used to make the PIA and the        allotment is not associated with the recycle content in a        reactant but rather on the recycle content of a monomer used to        make the reactant; or    -   6. A Recycle PIA manufacturer applies at least a portion of an        allotment to a reactant used to make a PIA to thereby obtain a        Recycle PIA, where the allotment was not obtained with the        transfer or purchase of the reactant and the allotment is        associated with the recycle content in the reactant; or    -   7. A Recycle PIA manufacturer applies at least a portion of an        allotment to a reactant used to make a PIA to thereby obtain a        Recycle PIA, where the allotment was not obtained with the        transfer or purchase of the reactant and the allotment is not        associated with the recycle content in the reactant but rather        with the recycle content of any monomers used to make the        reactant; or    -   8. A Recycle PIA manufacturer obtains an allotment having its        origin r-pyoil, and:        -   a. no portion of the allotment is applied to a reactant to            make PIA and instead at least a portion of the allotment is            applied to the PIA to make a Recycle PIA; or        -   b. less than the entire portion is applied to a reactant            used to make PIA and the remainder is stored in inventory or            is applied to future made PIA or is applied to existing            Recycle PIA in inventory to increase its recycle content            value.

In one embodiment or in combination with any mentioned embodiments, theRecycle PIA, or articles made thereby, can be offered for sale or soldas Recycle PIA containing or obtained with recycle content. The sale oroffer for sale can be accompanied with a certification or representationof the recycle content claim made in association with the Recycle PIA.

The designation of at least a portion of the Recycle PIA orolefin-containing effluent as corresponding to at least a portion of theallotment (e.g. allocation or credit) can occur through a variety ofmeans and according to the system employed by the Recycle PIAmanufacturer or the olefin-containing effluent manufacturer, which canvary from manufacturer to manufacturer. For example, the designation canoccur internally merely through a log entry in the books or files of themanufacturer or other inventory software program, or through anadvertisement or statement on a specification, on a package, on theproduct, by way of a logo associated with the product, by way of acertification declaration sheet associated with a product sold, orthrough formulas that compute the amount deducted from inventoryrelative to the amount of recycle content applied to a product.

Optionally, the Recycle PIA can be sold. In one embodiment or incombination with any mentioned embodiments, there is provided a methodof offering to sell or selling polymer and/or articles by:

-   -   a. A Recycle PIA manufacturer or an olefin-containing effluent        manufacturer, or any among their Family of Entities        (collectively the Manufacturer) obtains or generates a recycle        content allotment, and the allotment can be obtained by any of        the means described herein and can be deposited into a recycle        content inventory, the recycle content allotment having its        origin in r-pyoil,    -   b. converting a reactant in a synthetic process to make PIA, and        the reactant can be any reactant or a r-reactant,    -   c. designating (e.g. assigning or associating) a recycle content        to at least a portion of the PIA from a recycle content        inventory to make a Recycle PIA, where the inventory contains at        least one entry that is an allotment associated with r-pyoil.        The designation can be the amount of allotment deducted from        inventory, or the amount of recycle content declared or        determined by the Recycle PIA manufacturer in its accounts.        Thus, the amount of recycle content does not necessarily have to        be applied to the Recycle PIA product in a physical fashion. The        designation can be an internal designation to or by the        Manufacturer or a service provider in contractual relationship        to the Manufacturer, and    -   d. offering to sell or selling the Recycle PIA as containing or        obtained with recycle content corresponding at least in part        with such designation. The amount of recycle content represented        as contained in the Recycle PIA sold or offered for sale has a        relationship or linkage to the designation. The amount of        recycle content can be a 1:1 relationship in the amount of        recycle content declared on a Recycle PIA offered for sale or        sold and the amount of recycle content assigned or designated to        the Recycle PIA by the Recycle PIA manufacturer.

The steps described need not be sequential and can be independent fromeach other. For example, the step a) of obtaining an allotment and thestep of making Recycle PIA can be simultaneous.

As used throughout, the step of deducting an allotment from a recyclecontent inventory does not require its application to a Recycle PIAproduct. The deduction also does not mean that the quantity disappearsor is removed from the inventory logs. A deduction can be an adjustmentof an entry, a withdrawal, an addition of an entry as a debit, or anyother algorithm that adjusts inputs and outputs based on an amountrecycle content associated with a product and one or a cumulative amountof allotments on deposit in the inventory. For example, a deduction canbe a simple step of a reducing/debit entry from one column and anaddition/credit to another column within the same program or books, oran algorithm that automates the deductions and entries/additions and/orapplications or designations to a product slate. The step of applying anallotment to a PIA where such allotment was deducted from inventory alsodoes not require the allotment to be applied physically to a Recycle PIAproduct or to any document issued in association with the Recycle PIAproduct sold. For example, a Recycle PIA manufacturer may ship RecyclePIA product to a customer and satisfy the “application” of the allotmentto the Recycle PIA product by electronically transferring a recyclecontent credit to the customer.

There is also provided a use for r-pyoil, the use including convertingr-pyoil in a gas cracker furnace to make an olefin-containing effluent.olefin-containing effluent.

There is also provided a use for a r-pyoil that includes converting areactant in a synthetic process to make a PIA and applying at least aportion of an allotment to the PIAPIA, where the allotment is associatedwith r-pyoil or has its origin in an inventory of allotments where atleast one deposit made into the inventory is associated with r-pyoil.

In one embodiment or in combination with any mentioned embodiments,there is provided a PIAPIA that is obtained by any of the methodsdescribed above.

The reactant can be stored in a storage vessel and transferred to aRecycle PIA manufacturing facility by way of truck, pipe, or ship, or asfurther described below, the olefin-containing effluent productionfacility can be integrated with the PIA facility. The reactant may beshipped or transferred to the operator or facility that makes thepolymer and/or article.

In an embodiment, the process for making Recycle PIA can be anintegrated process. One such example is a process to make Recycle PIAby:

-   -   a. cracking r-pyoil to make an olefin-containing effluent        olefin-containing effluent; and    -   b. separating compounds in said olefin-containing effluent to        obtain a separated compound; and    -   c. reacting any reactant in a synthetic process to make a PIA;    -   d. depositing an allotment into an inventory of allotments, said        allotment originating from r-pyoil; and    -   e. applying any allotment from said inventory to the PIA to        thereby obtain a Recycle PIA.

In one embodiment or in combination with any mentioned embodiments, onemay integrate two or more facilities and make Recycle PIA. Thefacilities to make Recycle PIA, or the olefin-containing effluent, canbe stand-alone facilities or facilities integrated to each other. Forexample, one may establish a system of producing and consuming areactant, as follows:

-   -   a. provide an olefin-containing effluent manufacturing facility        configured to produce a reactant;    -   b. provide a PIA manufacturing facility having a reactor        configured to accept a reactant from the olefin-containing        effluent manufacturing facility; and    -   c. a supply system providing fluid communication between these        two facilities and capable of supplying a reactant from the        olefin-containing effluent manufacturing facility to the PIA        manufacturing facility,        wherein the olefin-containing effluent manufacturing facility        generates or participates in a process to generate allotments        and cracks r-pyoil, and:    -   (i) said allotments are applied to the reactants or to the PIA,        or    -   (ii) are deposited into an inventory of allotments, and        optionally an allotment is withdrawn from the inventory and        applied to the reactants or to the PIA.

The Recycle PIA manufacturing facility can make Recycle PIA by acceptingany reactant from the olefin-containing effluent manufacturing facilityand applying a recycle content to Recycle PIA made with the reactant bydeducting allotments from its inventory and applying them to the PIA.

In one embodiment or in combination with any mentioned embodiments,there is also provided a system for producing Recycle PIA as follows:

-   -   a. provide an olefin-containing effluent manufacturing facility        configured to produce an output composition comprising an        olefin-containing effluent;    -   b. provide a reactant manufacturing facility configured to        accept a compound separated from the olefin-containing effluent        and making, through a reaction scheme one or more downstream        products of said compound to make an output composition        comprising a reactant;    -   c. provide a PIA manufacturing facility having a reactor        configured to accept a reactant and making an output composition        comprising PIA; and    -   d. a supply system providing fluid communication between at        least two of these facilities and capable of supplying the        output composition of one manufacturing facility to another one        or more of said manufacturing facilities.

The PIA manufacturing facility can make Recycle PIA. In this system, theolefin-containing effluent manufacturing facility can have its output influid communication with the reactant manufacturing facility which inturn can have its output in fluid communication with the PIAmanufacturing facility. Alternatively, the manufacturing facilities ofa) and b) alone can be in fluid communication, or only b) and c). In thelatter case, the PIA manufacturing facility can make Recycle PIA bydeducting allotments from it recycle content inventory and applying themto the PIA. The allotments obtained and stored in inventory can beobtained by any of the methods described above,

The fluid communication can be gaseous or liquid or both. The fluidcommunication need not be continuous and can be interrupted by storagetanks, valves, or other purification or treatment facilities, so long asthe fluid can be transported from the manufacturing facility to thesubsequent facility through an interconnecting pipe network and withoutthe use of truck, train, ship, or airplane. Further, the facilities mayshare the same site, or in other words, one site may contain two or moreof the facilities. Additionally, the facilities may also share storagetank sites, or storage tanks for ancillary chemicals, or may also shareutilities, steam or other heat sources, etc., yet also be considered asdiscrete facilities since their unit operations are separate. A facilitywill typically be bounded by a battery limit.

In one embodiment or in combination with any mentioned embodiments, theintegrated process includes at least two facilities co-located within 5,or within 3, or within 2, or within 1 mile of each other (measured as astraight line). In one embodiment or in combination with any mentionedembodiments, at least two facilities are owned by the same Family ofEntities.

In an embodiment, there is also provided an integrated Recycle PIAgenerating and consumption system. This system includes:

-   -   a. provide an olefin-containing effluent manufacturing facility        configured to produce an output composition comprising an        olefin-containing effluent;    -   b. provide a reactant manufacturing facility configured to        accept a compound separated from the olefin-containing effluent        and making, through a reaction scheme one or more downstream        products of said compound to make an output composition        comprising a reactant;    -   c. provide a PIA manufacturing facility having a reactor        configured to accept a reactant and making an output composition        comprising PIA; and    -   d. a piping system interconnecting at least two of said        facilities, optionally with intermediate processing equipment or        storage facilities, capable of taking off the output composition        from one facility and accept said output at any one or more of        the other facilities.

The system does not necessarily require a fluid communication betweenthe two facilities, although fluid communication is desirable. Forexample, the compound separated from the olefin-containing effluent canbe delivered to the reactant facility through the interconnecting pipingnetwork that can be interrupted by other processing equipment, such astreatment, purification, pumps, compression, or equipment adapted tocombine streams, or storage facilities, all containing optionalmetering, valving, or interlock equipment. The equipment can be a fixedto the ground or fixed to structures that are fixed to the ground. Theinterconnecting piping does not need to connect to the reactant reactoror the cracker, but rather to a delivery and receiving point at therespective facilities. The interconnecting pipework need not connect allthree facilities to each other, but rather the interconnecting pipeworkcan be between facilities a)-b), or b)-c), or between a)-b)-c).

There is also provided a circular manufacturing process comprising:

-   -   1. providing a r-pyoil, and    -   2. cracking the r-pyoil to produce an olefin-containing        effluent, and        -   (i) reacting a compound separated from said            olefin-containing effluent to make a Recycle PIA, or        -   (ii) associating a recycle content allotment, obtained from            said r-pyoil, to the PIA made from compounds separated from            a non-recycle olefin-containing effluent, to produce a            Recycle PIA; and    -   3. taking back at least a portion of any of said Recycle PIA or        any other articles, compounds, or polymer made from said Recycle        PIA, as a feedstock to make said r-pyoil.

In the above described process, an entirely circular or closed loopprocess is provided in which Recycle PIA can be recycled multiple times.

Examples of articles that are included in PIA are fibers, yarns, tow,continuous filaments, staple fibers, rovings, fabrics, textiles, flake,film (e.g. polyolefin films), sheet, compounded sheet, plasticcontainers, and consumer articles.

In one embodiment or in combination with any mentioned embodiments, theRecycle PIA is a polymer or article of the same family or classificationof polymers or articles used to make r-pyoil.

As used herein, the terms “recycled waste,” “waste stream,” and“recycled waste stream” are used interchangeably to mean any type ofwaste or waste-containing stream that is reused in a production process,rather than being permanently disposed of (e.g., in a landfill orincinerator). The recycled waste stream is a flow or accumulation ofwaste from industrial and consumer sources that is at least in partrecovered. A recycled waste stream includes materials, products, andarticles (collectively “material(s)” when used alone). Waste materialscan be solid or liquid. Examples of a solid waste stream includeplastics, rubber (including tires), textiles, wood, biowaste, modifiedcelluloses, wet laid products, and any other material capable of beingpyrolyzed. Examples of liquid waste streams include industrial sludge,oils (including those derived from plants and petroleum), recovered lubeoil, or vegetable oil or animal oil, and any other chemical streams fromindustrial plants.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the recycledwaste stream that is pyrolyzed includes a stream containing at least inpart post-industrial, or post-consumer, or both a post-industrial andpost-consumer materials. In an embodiment or in combination with anyembodiment mentioned herein or in combination with any of the mentionedembodiments, a post-consumer material is one that has been used at leastonce for its intended application for any duration of time regardless ofwear, or has been sold to an end use customer, or which is discardedinto a recycle bin by any person or entity other than a manufacturer orbusiness engaged in the manufacture or sale of the material. In anembodiment or in combination with any embodiment mentioned herein or incombination with any of the mentioned embodiments, a post-industrialmaterial is one which has been created and has not been used for itsintended application, or has not been sold to the end use customer, ordiscarded by a manufacturer or any other entity engaged in the sale ofthe material. Examples of post-industrial materials include rework,regrind, scrap, trim, out of specification materials, and finishedmaterials transferred from a manufacturer to any downstream customer(e.g. manufacturer to wholesaler to distributor) but not yet used orsold to the end use customer.

The form of the recycled waste stream fed to a pyrolysis unit is notlimited, and can include any of the forms of articles, products,materials, or portions thereof. A portion of an article can take theform of sheets, extruded shapes, moldings, films, laminates, foampieces, chips, flakes, particles, agglomerates, briquettes, powder,shredded pieces, long strips, or randomly shaped pieces having a widevariety of shapes, or any other form other than the original form of thearticle and adapted to feed a pyrolysis unit.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the wastematerial is size reduced. Size reduction can occur through any means,including chopping, shredding, harrowing, confrication, pulverizing,cutting a feedstock, molding, compression, or dissolution in a solvent.

Recycled waste plastics can be isolated as one type of polymer stream ormay be a stream of mixed waste plastics. The plastics can be any organicsynthetic polymer that is solid at 25° C. at 1 atm. The plastics can bethermosetting, thermoplastic, or elastomeric plastics. Examples ofplastics include high density polyethylene and copolymers thereof, lowdensity polyethylene and copolymers thereof, polypropylene andcopolymers thereof, other polyolefins, polystyrene, polyvinyl chloride(PVC), polyvinylidene chloride (PVDC), polyesters including polyethyleneterephthalate, copolyesters and terephthalate copolyesters (e.g.containing residues of TMCD, CHDM, propylene glycol, or NPG monomers),polyethylene terephthalate, polyamides, poly(methyl methacrylate),polytetrafluoroethylene, acrylobutadienestyrene (ABS), polyurethanes,cellulosics and derivates thereof, epoxy, polyamides, phenolic resins,polyacetal, polycarbonates, polyphenylene-based alloys, polypropyleneand copolymers thereof, polystyrene, styrenic compounds, vinyl basedcompounds, styrene acrylonitrile, thermoplastic elastomers, and ureabased polymers and melamine containing polymers.

Suitable recycled waste plastics also include any of those having aresin ID code numbered 1-7 within the chasing arrow triangle establishedby the SPI. In an embodiment or in combination with any embodimentmentioned herein or in combination with any of the mentionedembodiments, the r-pyoil is made from a recycled waste stream at least aportion of which contains plastics that are not generally recycled.These would include plastics having numbers 3 (polyvinyl chloride), 5(polypropylene), 6 (polystyrene), and 7 (other). In an embodiment or incombination with any embodiment mentioned herein or in combination withany of the mentioned embodiments, the waste stream that is pyrolyzedcontains less than 10 weight percent, or not more than 5 weight percent,or not more than 3 weight percent, or not more than 2 weight percent, ornot more than 1 weight percent, or not more than 0.5 weight percent, ornot more than 0.2 weight percent, or not more than 0.1 weight percent,or not more and 0.05 weight percent plastics with a number 3 designation(polyvinyl chloride), or optionally plastics with a number 3 and 6designation, or optionally with a number 3, 6 and 7 designation.

Examples of recycled rubber include natural and synthetic rubber. Theform of the rubber is not limited and includes tires.

Examples of recycled waste wood include soft and hard woods, chipped,pulped, or as finished articles. The source of much waste wood isindustrial, construction, or demolition.

Examples of recycled biowaste includes household biowaste (e.g. food),green or garden biowaste, and biowaste from the industrial foodprocessing industry.

Examples of recycled textiles includes natural and/or synthetic fibers,rovings, yarns, nonwoven webs, cloth, fabrics and products made from orcontaining any of the aforementioned items. Textiles can be woven,knitted, knotted, stitched, tufted, pressing of fibers together such aswould be done in a felting operation, embroidered, laced, crocheted,braided, or nonwoven webs and materials. Textiles include fabrics, andfibers separated from a textile or other product containing fibers,scrap or off spec fibers or yarns or fabrics, or any other source ofloose fibers and yarns. A textile also includes staple fibers,continuous fibers, threads, tow bands, twisted and/or spun yarns, greyfabrics made from yarns, finished fabrics produced by wet processinggray fabrics, and garments made from the finished fabrics or any otherfabrics. Textiles include apparels, interior furnishings, and industrialtypes of textiles.

Examples of recycled textiles in the apparel category (things humanswear or made for the body) include sports coats, suits, trousers andcasual or work pants, shirts, socks, sportswear, dresses, intimateapparel, outerwear such as rain jackets, cold temperature jackets andcoats, sweaters, protective clothing, uniforms, and accessories such asscarves, hats, and gloves. Examples of textiles in the interiorfurnishing category include furniture upholstery and slipcovers, carpetsand rugs, curtains, bedding such as sheets, pillow covers, duvets,comforters, mattress covers; linens, tablecloths, towels, washcloths,and blankets. Examples of industrial textiles include transportation(auto, airplanes, trains, buses) seats, floor mats, trunk liners, andheadliners; outdoor furniture and cushions, tents, backpacks, luggage,ropes, conveyor belts, calendar roll felts, polishing cloths, rags, soilerosion fabrics and geotextiles, agricultural mats and screens, personalprotective equipment, bullet proof vests, medical bandages, sutures,tapes, and the like.

The recycled nonwoven webs can also be dry laid nonwoven webs. Examplesof suitable articles that may be formed from dry laid nonwoven webs asdescribed herein can include those for personal, consumer, industrial,food service, medical, and other types of end uses. Specific examplescan include, but are not limited to, baby wipes, flushable wipes,disposable diapers, training pants, feminine hygiene products such assanitary napkins and tampons, adult incontinence pads, underwear, orbriefs, and pet training pads. Other examples include a variety ofdifferent dry or wet wipes, including those for consumer (such aspersonal care or household) and industrial (such as food service, healthcare, or specialty) use. Nonwoven webs can also be used as padding forpillows, mattresses, and upholstery, batting for quilts and comforters.In the medical and industrial fields, nonwoven webs of the presentinvention may be used for medical and industrial face masks, protectiveclothing, caps, and shoe covers, disposable sheets, surgical gowns,drapes, bandages, and medical dressings. Additionally, nonwoven webs maybe used for environmental fabrics such as geotextiles and tarps, oil andchemical absorbent pads, as well as building materials such as acousticor thermal insulation, tents, lumber and soil covers and sheeting.Nonwoven webs may also be used for other consumer end use applications,such as for, carpet backing, packaging for consumer, industrial, andagricultural goods, thermal or acoustic insulation, and in various typesof apparel. The dry laid nonwoven webs may also be used for a variety offiltration applications, including transportation (e.g., automotive oraeronautical), commercial, residential, industrial, or other specialtyapplications. Examples can include filter elements for consumer orindustrial air or liquid filters (e.g., gasoline, oil, water), includingnanofiber webs used for microfiltration, as well as end uses like teabags, coffee filters, and dryer sheets. Further, nonwoven webs may beused to form a variety of components for use in automobiles, including,but not limited to, brake pads, trunk liners, carpet tufting, and underpadding.

The recycled textiles can include single type or multiple type ofnatural fibers and/or single type or multiple type of synthetic fibers.Examples of textile fiber combinations include all natural, allsynthetic, two or more type of natural fibers, two or more types ofsynthetic fibers, one type of natural fiber and one type of syntheticfiber, one type of natural fibers and two or more types of syntheticfibers, two or more types of natural fibers and one type of syntheticfibers, and two or more types of natural fibers and two or more types ofsynthetic fibers.

Examples of recycled wet laid products include cardboard, office paper,newsprint and magazine, printing and writing paper, sanitary,tissue/toweling, packaging/container board, specialty papers, apparel,bleached board, corrugated medium, wet laid molded products, unbleachedKraft, decorative laminates, security paper and currency, grand scalegraphics, specialty products, and food and drink products.

Examples of modified cellulose include cellulose acetate, cellulosediacetate, cellulose triacetate, regenerated cellulose such a viscose,rayon, and Lyocel™ products, in any form, such as tow bands, staplefibers, continuous fibers, films, sheets, molded or stamped products,and contained in or on any article such as cigarette filter rods,ophthalmic products, screwdriver handles, optical films, and coatings.

Examples of recycled vegetable oil or animal oil include the oilsrecovered from animal processing facilities and waste from restaurants.

The source for obtaining recycled post-consumer or post-industrial wasteis not limited and can include waste present in and/or separated frommunicipal solid waste streams (“MSW”). For example, an MSW stream can beprocessed and sorted to several discrete components, including textiles,fibers, papers, wood, glass, metals, etc. Other sources of textilesinclude those obtained by collection agencies, or by or for or on behalfof textile brand owners or consortiums or organizations, or frombrokers, or from postindustrial sources such as scrap from mills orcommercial production facilities, unsold fabrics from wholesalers ordealers, from mechanical and/or chemical sorting or separationfacilities, from landfills, or stranded on docks or ships.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the feed to thepyrolysis unit can comprise at least 30, or at least 35, or at least 40,or at least 45, or at least 50, or at least 55, or at least 60, or atleast 65, or at least 70, or at least 75, or at least 80, or at least85, or at least 90, or at least 95, or at least 99, in each case weightpercent of at least one, or at least two, or at least three, or at leastfour, or at least five, or at least six different kinds of recycledwaste. Reference to a “kind” is determined by resin ID code 1-7. In anembodiment or in combination with any embodiment mentioned herein or incombination with any of the mentioned embodiments, the feed to thepyrolysis unit contains less than 25, or not more than 20, or not morethan 15, or not more than 10, or not more than 5, or not more than 1, ineach case weight percent of polyvinyl chloride and/or polyethyleneterephthalate. In an embodiment or in combination with any embodimentmentioned herein or in combination with any of the mentionedembodiments, the recycled waste stream contains at least one, two, orthree kinds of plasticized plastics.

FIG. 2 depicts an exemplary pyrolysis system 110 that may be employed toat least partially convert one or more recycled waste, particularlyrecycled plastic waste, into various useful pyrolysis-derived products.It should be understood that the pyrolysis system shown in FIG. 2 isjust one example of a system within which the present disclosure can beembodied. The present disclosure may find application in a wide varietyof other systems where it is desirable to efficiently and effectivelypyrolyze recycled waste, particularly recycled plastic waste, intovarious desirable end products. The exemplary pyrolysis systemillustrated in FIG. 2 will now be described in greater detail.

As shown in FIG. 2, the pyrolysis system 110 may include a waste plasticsource 112 for supplying one or more waste plastics to the system 110.The plastic source 112 can be, for example, a hopper, storage bin,railcar, over-the-road trailer, or any other device that may hold orstore waste plastics. In an embodiment or in combination with any of theembodiments mentioned herein, the waste plastics supplied by the plasticsource 112 can be in the form of solid particles, such as chips, flakes,or a powder. Although not depicted in FIG. 2, the pyrolysis system 110may also comprise additional sources of other types of recycled wastesthat may be utilized to provide other feed types to the system 110.

In an embodiment or in combination with any of the embodiments mentionedherein, the waste plastics can include one or more post-consumer wasteplastic such as, for example, high density polyethylene, low densitypolyethylene, polypropylene, other polyolefins, polystyrene, polyvinylchloride (PVC), polyvinylidene chloride (PVDC), polyethyleneterephthalate, polyamides, poly(methyl methacrylate),polytetrafluoroethylene, or combinations thereof. In an embodiment or incombination with any of the embodiments mentioned herein, the wasteplastics may include high density polyethylene, low densitypolyethylene, polypropylene, or combinations thereof. As used herein,“post-consumer” refers to non-virgin plastics that have been previouslyintroduced into the consumer market.

In an embodiment or in combination with any of the embodiments mentionedherein, a waste plastic-containing feed may be supplied from the plasticsource 112. In an embodiment or in combination with any of theembodiments mentioned herein, the waste plastic-containing feed cancomprise, consist essentially of, or consist of high densitypolyethylene, low density polyethylene, polypropylene, otherpolyolefins, polystyrene, polyvinyl chloride (PVC), polyvinylidenechloride (PVDC), polyethylene terephthalate, polyamides, poly(methylmethacrylate), polytetrafluoroethylene, or combinations thereof.

In an embodiment or in combination with any of the embodiments mentionedherein, the waste plastic-containing feed can comprise at least 30, orat least 35, or at least 40, or at least 45, or at least 50, or at least55, or at least 60, or at least 65, or at least 70, or at least 75, orat least 80, or at least 85, or at least 90, or at least 95, or at least99, in each case weight percent of at least one, two, three, or fourdifferent kinds of waste plastic. In an embodiment or in combinationwith any of the embodiments mentioned herein, the plastic waste maycomprise not more than 25, or not more than 20, or not more than 15, ornot more than 10, or not more than 5, or not more than 1, in each caseweight percent of polyvinyl chloride and/or polyethylene terephthalate.In an embodiment or in combination with any of the embodiments mentionedherein, the waste plastic-containing feed can comprise at least one,two, or three kinds of plasticized plastics. Reference to a “kind” isdetermined by resin ID code 1-7.

As depicted in FIG. 2, the solid waste plastic feed from the plasticsource 112 can be supplied to a feedstock pretreatment unit 114. Whilein the feedstock pretreatment unit 114, the introduced waste plasticsmay undergo a number of pretreatments to facilitate the subsequentpyrolysis reaction. Such pretreatments may include, for example,washing, mechanical agitation, flotation, size reduction or anycombination thereof. In an embodiment or in combination with any of theembodiments mentioned herein, the introduced plastic waste may besubjected to mechanical agitation or subjected to size reductionoperations to reduce the particle size of the plastic waste. Suchmechanical agitation can be supplied by any mixing, shearing, orgrinding device known in the art which may reduce the average particlesize of the introduced plastics by at least 10, or at least 25, or atleast 50, or at least 75, in each case percent.

Next, the pretreated plastic feed can be introduced into a plastic feedsystem 116. The plastic feed system 116 may be configured to introducethe plastic feed into the pyrolysis reactor 118. The plastic feed system116 can comprise any system known in the art that is capable of feedingthe solid plastic feed into the pyrolysis reactor 118. In an embodimentor in combination with any of the embodiments mentioned herein, theplastic feed system 116 can comprise a screw feeder, a hopper, apneumatic conveyance system, a mechanic metal train or chain, orcombinations thereof.

While in the pyrolysis reactor 118, at least a portion of the plasticfeed may be subjected to a pyrolysis reaction that produces a pyrolysiseffluent comprising a pyrolysis oil (e.g., r-pyoil) and a pyrolysis gas(e.g., r-pyrolysis gas). The pyrolysis reactor 118 can be, for example,an extruder, a tubular reactor, a tank, a stirred tank reactor, a riserreactor, a fixed bed reactor, a fluidized bed reactor, a rotary kiln, avacuum reactor, a microwave reactor, an ultrasonic or supersonicreactor, or an autoclave, or a combination of these reactors.

Generally, pyrolysis is a process that involves the chemical and thermaldecomposition of the introduced feed. Although all pyrolysis processesmay be generally characterized by a reaction environment that issubstantially free of oxygen, pyrolysis processes may be furtherdefined, for example, by the pyrolysis reaction temperature within thereactor, the residence time in the pyrolysis reactor, the reactor type,the pressure within the pyrolysis reactor, and the presence or absenceof pyrolysis catalysts.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis reaction can involve heating and converting theplastic feed in an atmosphere that is substantially free of oxygen or inan atmosphere that contains less oxygen relative to ambient air. In anembodiment or in combination with any of the embodiments mentionedherein, the atmosphere within the pyrolysis reactor 118 may comprise notmore than 5, or not more than 4, or not more than 3, or not more than 2,or not more than 1, or not more than 0.5, in each case weight percent ofoxygen gas.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis process may be carried out in the presence of aninert gas, such as nitrogen, carbon dioxide, and/or steam. Additionally,or alternatively, in an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis process can be carried outin the presence of a reducing gas, such as hydrogen and/or carbonmonoxide.

In an embodiment or in combination with any of the embodiments mentionedherein, the temperature in the pyrolysis reactor 118 can be adjusted toas to facilitate the production of certain end products. In anembodiment or in combination with any of the embodiments mentionedherein, the pyrolysis temperature in the pyrolysis reactor 118 can be atleast 325° C., or at least 350° C., or at least 375° C., or at least400° C., or at least 425° C., or at least 450° C., or at least 475° C.,or at least 500° C., or at least 525° C., or at least 550° C., or atleast 575° C., or at least 600° C., or at least 625° C., or at least650° C., or at least 675° C., or at least 700° C., or at least 725° C.,or at least 750° C., or at least 775° C., or at least 800° C.Additionally, or alternatively, in an embodiment or in combination withany of the embodiments mentioned herein, the pyrolysis temperature inthe pyrolysis reactor 118 can be not more than 1,100° C., or not morethan 1,050° C., or not more than 1,000° C., or not more than 950° C., ornot more than 900° C., or not more than 850° C., or not more than 800°C., or not more than 750° C., or not more than 700° C., or not more than650° C., or not more than 600° C., or not more than 550° C., or not morethan 525° C., or not more than 500° C., or not more than 475° C., or notmore than 450° C., or not more than 425° C., or not more than 400° C. Inan embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis temperature in the pyrolysis reactor 118 can rangefrom 325 to 1,100° C., 350 to 900° C., 350 to 700° C., 350 to 550° C.,350 to 475° C., 500 to 1,100° C., 600 to 1,100° C., or 650 to 1,000° C.

In an embodiment or in combination with any of the embodiments mentionedherein, the residence times of the pyrolysis reaction can be at least 1,or at least 2, 3 or at least, or at least 4, in each case seconds, or atleast 10, or at least 20, or at least 30, or at least 45, or at least60, or at least 75, or at least 90, in each case minutes. Additionally,or alternatively, in an embodiment or in combination with any of theembodiments mentioned herein, the residence times of the pyrolysisreaction can be not more than 6 hours, or not more than 5, or not morethan 4, or not more than 3, 2 or not more than, 1 or not more than 0.5,1, or not more than 0.5, in each case hours. In an embodiment or incombination with any of the embodiments mentioned herein, the residencetimes of the pyrolysis reaction can range from 30 minutes to 4 hours, or30 minutes to 3 hours, or 1 hour to 3 hours, or 1 hour to 2 hours.

In an embodiment or in combination with any of the embodiments mentionedherein, the pressure within the pyrolysis reactor 118 can be maintainedat a pressure of at least 0.1, or at least 0.2, or at least 0.3, in eachcase bar and/or not more than 60, or not more than 50, or not more than40, or not more than 30, or not more than 20, or not more than 10, ornot more than 8, or not more than 5, or not more than 2, or not morethan 1.5, or not more than 1.1, in each case bar. In an embodiment or incombination with any of the embodiments mentioned herein, the pressurewithin the pyrolysis reactor 18 can be maintained at about atmosphericpressure or within the range of 0.1 to 100 bar, or 0.1 to 60 bar, or 0.1to 30 bar, or 0.1 to 10 bar, or 1.5 bar, 0.2 to 1.5 bar, or 0.3 to 1.1bar.

In an embodiment or in combination with any of the embodiments mentionedherein, a pyrolysis catalyst may be introduced into the plastic feedprior to introduction into the pyrolysis reactor 118 and/or introduceddirectly into the pyrolysis reactor 118 to produce an r-catalytic pyoil,or an r-pyoil made by a catalytic pyrolysis process. In an embodiment orin combination with any embodiment mentioned herein or in combinationwith any of the embodiments mentioned herein, the catalyst can comprise:(i) a solid acid, such as a zeolite (e.g., ZSM-5, Mordenite, Beta,Ferrierite, and/or zeolite-Y); (ii) a super acid, such as sulfonated,phosphated, or fluorinated forms of zirconia, titania, alumina,silica-alumina, and/or clays; (iii) a solid base, such as metal oxides,mixed metal oxides, metal hydroxides, and/or metal carbonates,particularly those of alkali metals, alkaline earth metals, transitionmetals, and/or rare earth metals; (iv) hydrotalcite and other clays; (v)a metal hydride, particularly those of alkali metals, alkaline earthmetals, transition metals, and/or rare earth metals; (vi) an aluminaand/or a silica-alumina; (vii) a homogeneous catalyst, such as a Lewisacid, a metal tetrachloroaluminate, or an organic ionic liquid; (viii)activated carbon; or (ix) combinations thereof.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis reaction in the pyrolysis reactor 118 occurs inthe substantial absence of a catalyst, particularly the above-referencedcatalysts. In such embodiments, a non-catalytic, heat-retaining inertadditive may still be introduced into the pyrolysis reactor 118, such assand, in order to facilitate the heat transfer within the reactor 118.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis reaction in the pyrolysis reactor 118 may occur inthe substantial absence of a pyrolysis catalyst, at a temperature in therange of 350 to 550° C., at a pressure ranging from 0.1 to 60 bar, andat a residence time of 0.2 seconds to 4 hours, or 0.5 hours to 3 hours.

Referring again to FIG. 2, the pyrolysis effluent 120 exiting thepyrolysis reactor 118 generally comprises pyrolysis gas, pyrolysisvapors, and residual solids. As used herein, the vapors produced duringthe pyrolysis reaction may interchangeably be referred to as a“pyrolysis oil,” which refers to the vapors when condensed into theirliquid state. In an embodiment or in combination with any of theembodiments mentioned herein, the solids in the pyrolysis effluent 20may comprise particles of char, ash, unconverted plastic solids, otherunconverted solids from the feedstock, and/or spent catalyst (if acatalyst is utilized).

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis effluent 120 may comprise at least 20, or at least25, or at least 30, or at least 40, or at least 45, or at least 50, orat least 55, or at least 60, or at least 65, or at least 70, or at least75, or at least or at least 80, in each case weight percent of thepyrolysis vapors, which may be subsequently condensed into the resultingpyrolysis oil (e.g., r-pyoil). Additionally, or alternatively, in anembodiment or in combination with any of the embodiments mentionedherein, the pyrolysis effluent 120 may comprise not more than 99, or notmore than 95, or not more than 90, or not more than 85, or not more than80, or not more than 75, or not more than 70, or not more than 65, ornot more than 60, or not more than 55, or not more than 50, or not morethan 45, or not more than 40, or not more than 35, or not more than 30,in each case weight percent of the pyrolysis vapors. In an embodiment orin combination with any of the embodiments mentioned herein, thepyrolysis effluent 120 may comprise in the range of 20 to 99 weightpercent, 40 to 90 weight percent, or 55 to 90 weight percent of thepyrolysis vapors.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis effluent 120 may comprise at least 1, or at least5, or at least 6, or at least 7, or at least 8, or at least 9, or atleast 10, or at least 11, or at least 12, in each case weight percent ofthe pyrolysis gas (e.g., r-pyrolysis gas). As used herein, a “pyrolysisgas” refers to a composition that is produced via pyrolysis and is a gasat standard temperature and pressure (STP). Additionally, oralternatively, in an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis effluent 20 may comprise notmore than 90, or not more than 85, or not more than 80, or not more than75, or not more than 70, or not more than 65, or not more than 60, ornot more than 55, or not more than 50, or not more than 45, or not morethan 40, or not more than 35, or not more than 30, or not more than 25,or not more than 20, or not more than 15, in each case weight percent ofthe pyrolysis gas. In an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis effluent 120 may comprise 1to 90 weight percent, or 5 to 60 weight percent, or 10 to 60 weightpercent, or 10 to 30 weight percent, or 5 to 30 weight percent of thepyrolysis gas.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis effluent 120 may comprise not more than 15, or notmore than 10, or not more than 9, or not more than 8, or not more than7, or not more than 6, or not more than 5, or not more than 4 or notmore than 3, in each case weight percent of the residual solids.

In one embodiment or in combination of any mentioned embodiments, thereis provided a cracker feed stock composition containing pyrolysis oil(r-pyoil), and the r-pyoil composition contains recycle contentcatalytic pyrolysis oil (r-catalytic pyoil) and a recycle contentthermal pyrolysis oil (r-thermal pyoil). An r-thermal pyoil is pyoilmade without the addition of a pyrolysis catalyst. The cracker feedstockcan include at least 5, 10, 15, or 20 weight percent r-catalytic pyoil,optionally that has been hydrotreated. The r-pyoil containing t-thermalpyoil and r-catalytic pyoil can be cracked according to any of theprocesses described herein to provide an olefin-containing effluentstream. The r-catalytic pyoil can be blended with r-thermal pyoil toform a blended stream cracked in the cracker unit. Optionally, theblended stream can contain not more than 10, 5, 3, 2, 1 weight percentof r-catalytic pyoil that has not been hydrotreated.

In one embodiment or in combination with any mentioned embodiment, ther-pyoil does not contain r-catalytic pyoil.

As depicted in FIG. 2, the conversion effluent 120 from the pyrolysisreactor 118 can be introduced into a solids separator 122. The solidsseparator 122 can be any conventional device capable of separatingsolids from gas and vapors such as, for example, a cyclone separator ora gas filter or combination thereof. In an embodiment or in combinationwith any of the embodiments mentioned herein, the solids separator 122removes a substantial portion of the solids from the conversion effluent120. In an embodiment or in combination with any of the embodimentsmentioned herein, at least a portion of the solid particles 24 recoveredin the solids separator 122 may be introduced into an optionalregenerator 126 for regeneration, generally by combustion. Afterregeneration, at least a portion of the hot regenerated solids 128 canbe introduced directly into the pyrolysis reactor 118. In an embodimentor in combination with any of the embodiments mentioned herein, at leasta portion of the solid particles 124 recovered in the solids separator122 may be directly introduced back into the pyrolysis reactor 118,especially if the solid particles 124 contain a notable amount ofunconverted plastic waste. Solids can be removed from the regenerator126 through line 145 and discharged out of the system.

Turning back to FIG. 2, the remaining gas and vapor conversion products130 from the solids separator 122 may be introduced into a fractionator132. In the fractionator 132, at least a portion of the pyrolysis oilvapors may be separated from the pyrolysis gas to thereby form apyrolysis gas product stream 134 and a pyrolysis oil vapor stream 136.Suitable systems to be used as the fractionator 132 may include, forexample, a distillation column, a membrane separation unit, a quenchtower, a condenser, or any other known separation unit known in the art.In an embodiment or in combination with any of the embodiments mentionedherein, any residual solids 146 accrued in the fractionator 132 may beintroduced in the optional regenerator 126 for additional processing.

In an embodiment or in combination with any of the embodiments mentionedherein, at least a portion of the pyrolysis oil vapor stream 136 may beintroduced into a quench unit 138 in order to at least partially quenchthe pyrolysis vapors into their liquid form (i.e., the pyrolysis oil).The quench unit 138 may comprise any suitable quench system known in theart, such as a quench tower. The resulting liquid pyrolysis oil stream140 may be removed from the system 110 and utilized in the otherdownstream applications described herein. In an embodiment or incombination with any of the embodiments mentioned herein, the liquidpyrolysis oil stream 140 may not be subjected to any additionaltreatments, such as hydrotreatment and/or hydrogenation, prior to beingutilized in any of the downstream applications described herein.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein, at leasta portion of the pyrolysis oil vapor stream 136 may be introduced into ahydroprocessing unit 142 for further refinement. The hydroprocessingunit 142 may comprise a hydrocracker, a catalytic cracker operating witha hydrogen feed stream, a hydrotreatment unit, and/or a hydrogenationunit. While in the hydroprocessing unit 142, the pyrolysis oil vaporstream 136 may be treated with hydrogen and/or other reducing gases tofurther saturate the hydrocarbons in the pyrolysis oil and removeundesirable byproducts from the pyrolysis oil. The resultinghydroprocessed pyrolysis oil vapor stream 144 may be removed andintroduced into the quench unit 138. Alternatively, the pyrolysis oilvapor may be cooled, liquified, and then treated with hydrogen and/orother reducing gases to further saturate the hydrocarbons in thepyrolysis oil. In this case, the hydrogenation or hydrotreating isperformed in a liquid phase pyrolysis oil. No quench step is required inthis embodiment post-hydrogenation or post-hydrotreating.

The pyrolysis system 110 described herein may produce a pyrolysis oil(e.g., r-pyoil) and pyrolysis gases (e.g., r-pyrolysis gas) that may bedirectly used in various downstream applications based on theirdesirable formulations. The various characteristics and properties ofthe pyrolysis oils and pyrolysis gases are described below. It should benoted that, while all of the following characteristics and propertiesmay be listed separately, it is envisioned that each of the followingcharacteristics and/or properties of the pyrolysis oils or pyrolysisgases are not mutually exclusive and may be combined and present in anycombination.

The pyrolysis oil may predominantly comprise hydrocarbons having from 4to 30 carbon atoms per molecule (e.g., C4 to C30 hydrocarbons). As usedherein, the term “Cx” or “Cx hydrocarbon,” refers to a hydrocarboncompound including x total carbons per molecule, and encompasses allolefins, paraffins, aromatics, and isomers having that number of carbonatoms. For example, each of normal, iso, and tert butane and butene andbutadiene molecules would fall under the general description “C4.”

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil fed to the cracking furnace may have a C₄-C₃₀hydrocarbon content of at least 55, or at least 60, or at least 65, orat least 70, or at least 75, or at least 80, or at least 85, or at least90, or at least 95, in each case weight percent based on the weight ofthe pyrolysis oil.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil fed to the furnace can predominantly compriseC₅-C₂₅, C₅-C₂₂, or C₅-C₂₀hydrocarbons, or may comprise at least about55, or at least 60, or at least 65, or at least 70, or at least 75, orat least 80, or at least 85, or at least 90, or at least 95, in eachcase weight percent of C₅-C₂₅, C₅-C₂₂, or C₅-C₂₀hydrocarbons, based onthe weight of the pyrolysis oil.

The gas furnace can tolerate a wide variety of hydrocarbon numbers inthe pyrolysis oil feedstock, thereby avoiding the necessity forsubjecting a pyrolysis oil feedstock to separation techniques to delivera smaller or lighter hydrocarbon cut to the cracker furnace. In oneembodiment or in any of the mentioned embodiments, the pyrolysis oilafter delivery from a pyrolysis manufacturer is not subjected aseparation process for separating a heavy hydrocarbon cut from a lighterhydrocarbon cut, relative to each other, prior to feeding the pyrolysisoil to a cracker furnace. The feed of pyrolysis oil to a gas furnaceallows one to employ a pyrolysis oil that contains heavy tail ends orhigher carbon numbers at or above 12. In one embodiment or in any of thementioned embodiments, the pyrolysis oil fed to a cracker furnace is aC₅ to C₂₅ hydrocarbon stream containing at least 3 wt. %, or at least 5wt. %, or at least 8 wt. %, or at least 10 wt. %, or at least 12 wt. %,or at least 15 wt. %, or at least 18 wt. %, or at least 20 wt. %, or atleast 25 wt. % or at least 30 wt. %, or at least 35 wt. %, or at least40 wt. %, or at least 45 wt. %, or at least 50 wt. %, or at least 55 wt.%, or at least 60 wt. % hydrocarbons within a range from C₁₂ to C₂₅,inclusive, or within a range of C₁₄ to C₂₅, inclusive, or within a rangeof C₁₆ to C₂₅, inclusive.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a C₆ to C₁₂ hydrocarbon content of atleast 10, or at least 15, or at least 20, or at least 25, or at least30, or at least 35, or at least 40, or at least 45, or at least 50, orat least 55, in each case weight percent, based on the weight of thepyrolysis oil. Additionally, or alternatively, in an embodiment or incombination with any of the embodiments mentioned herein, the pyrolysisoil may have a C6-C12 hydrocarbon content of not more than 95, or notmore than 90, or not more than 85, or not more than 80, or not more than75, or not more than 70, or not more than 65, or not more than 60, ineach case weight percent. In an embodiment or in combination with any ofthe embodiments mentioned herein, the pyrolysis oil may have a C6-C12hydrocarbon content in the range of 10 to 95 weight percent, 20 to 80weight percent, or 35 to 80 weight percent.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a C₁₃ to C₂₃ hydrocarbon content ofat least 1, or at least 5, or at least 10, or at least 15, or at least20, or at least 25, or at least 30, in each case weight percent.Additionally, or alternatively, in an embodiment or in combination withany of the embodiments mentioned herein, the pyrolysis oil may have aC₁₃ to C₂₃ hydrocarbon content of not more than 80, or not more than 75,or not more than 70, or not more than 65, or not more than 60, or notmore than 55, or not more than 50, or not more than 45, or not more than40, in each case weight percent. In an embodiment or in combination withany of the embodiments mentioned herein, the pyrolysis oil may have aC₁₃ to C₂₃ hydrocarbon content in the range of 1 to 80 weight percent, 5to 65 weight percent, or 10 to 60 weight percent.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyrolysis oil, or r-pyoil fed to a cracker furnace, orr-pyoil fed to a cracker furnace that, prior to feeding-pyoil, accepts apredominately C₂-C₄ feedstock (and the mention of r-pyoil or pyrolysisoil throughout includes any of these embodiments), may have a C₂₄₊hydrocarbon content of at least 1, or at least 2, or at least 3, or atleast 4, or at least 5, in each case weight percent. Additionally, oralternatively, in an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis oil may have a C₂₄₊hydrocarbon content of not more than 15, or not more than 10, or notmore than 9, or not more than 8, or not more than 7, or not more than 6,in each case weight percent. In an embodiment or in combination with anyof the embodiments mentioned herein, the pyrolysis oil may have a C₂₄₊hydrocarbon content in the range of 1 to 15 weight percent, 3 to 15weight percent, 2 to 5 weight percent, or 5 to 10 weight percent.

The pyrolysis oil may also include various amounts of olefins,aromatics, and other compounds. In an embodiment or in combination withany of the embodiments mentioned herein, the pyrolysis oil includes atleast 1, or at least 2, or at least 5, or at least 10, or at least 15,or at least 20, in each case weight percent olefins and/or aromatics.Additionally, or alternatively, in an embodiment or in combination withany of the embodiments mentioned herein, the pyrolysis oil may includenot more than 50, or not more than 45, or not more than 40, or not morethan 35, or not more than 30, or not more than 25, or not more than 20,or not more than 15, or not more than 10, or not more than 5, or notmore than 2, or not more than 1, in each case weight percent olefinsand/or aromatics.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have an aromatic content of not more than25, or not more than 20, or not more than 15, or not more than 14, ornot more than 13, or not more than 12, or not more than 11, or not morethan 10, or not more than 9, or not more than 8, or not more than 7, ornot more than 6, or not more than 5, or not more than 4, or not morethan 3, or not more than 2, or not more than 1, in each case weightpercent. In one embodiment or in combination with any mentionedembodiments, the pyrolysis oil has an aromatic content that is nothigher than 15, or not more than 10, or not more than 8, or not morethan 6, in each case weight percent.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a naphthene content of at least 1, orat least 2, or at least 3, or at least 4, or at least 5, or at least 6,or at least 7, or at least 8, or at least 9, or at least 10, or at least11, or at least 12, or at least 13, or at least 14, or at least 15, ineach case weight percent. Additionally, or alternatively, in anembodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a naphthene content of not more than50, or not more than 45, or not more than 40, or not more than 35, ornot more than 30, or not more than 25, or not more than 20, or not morethan 10, or not more than 5, or not more than 2, or not more than 1, ornot more than 0.5, or no detectable amount, in each case weight percent.In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a naphthene content of not more than5, or not more than 2, or not more than 1 wt. %, or no detectableamount, or naphthenes. Alternatively, the pyrolysis oil may contain inthe range of 1 to 50 weight percent, 5 to 50 weight percent, or 10 to 45weight percent naphthenes, especially if the r-pyoil was subjected to ahydrotreating process.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a paraffin content of at least 25, orat least 30, or at least 35, or at least 40, or at least 45, or at least50, in each case weight percent. Additionally, or alternatively, in anembodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a paraffin content of not more than90, or not more than 85, or not more than 80, or not more than 75, ornot more than 70, or not more than 65, or not more than 60, or not morethan 55, in each case weight percent. In an embodiment or in combinationwith any of the embodiments mentioned herein, the pyrolysis oil may havea paraffin content in the range of 25 to 90 weight percent, 35 to 90weight percent, or 40 to 80, or 40-70, or 40-65 weight percent.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have an n-paraffin content of at least 5,or at least 10, or at least 15, or at least 25, or at least 30, or atleast 35, or at least 40, or at least 45, or at least 50, in each caseweight percent. Additionally, or alternatively, in an embodiment or incombination with any of the embodiments mentioned herein, the pyrolysisoil may have an n-paraffin content of not more than 90, or not more than85, or not more than 80, or not more than 75, or not more than 70, ornot more than 65, or not more than 60, or not more than 55, in each caseweight percent. In an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis oil may have an n-paraffincontent in the range of 25 to 90 weight percent, 35 to 90 weightpercent, or 40-70, or 40-65, or 50 to 80 weight percent.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a paraffin to olefin weight ratio ofat least 0.2:1, or at least 0.3:1, or at least 0.4:1, or at least 0.5:1,or at least 0.6:1, or at least 0.7:1, or at least 0.8:1, or at least0.9:1, or at least 1:1. Additionally, or alternatively, in an embodimentor in combination with any of the embodiments mentioned herein, thepyrolysis oil may have a paraffin to olefin weight ratio not more than3:1, or not more than 2.5:1, or not more than 2:1, or not more than1.5:1, or not more than 1.4:1, or not more than 1.3:1. In an embodimentor in combination with any of the embodiments mentioned herein, thepyrolysis oil may have a paraffin to olefin weight ratio in the range of0.2:1 to 5:1, or 1:1 to 4.5:1, or 1.5:1 to 5:1, or 1.5:1:4.5:1, or 0.2:1to 4:1, or 0.2:1 to 3:1, 0.5:1 to 3:1, or 1:1 to 3:1.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have an n-paraffin to i-paraffin weightratio of at least 0.001:1, or at least 0.1:1, or at least 0.2:1, or atleast 0.5:1, or at least 1:1, or at least 2:1, or at least 3:1, or atleast 4:1, or at least 5:1, or at least 6:1, or at least 7:1, or atleast 8:1, or at least 9:1, or at least 10:1, or at least 15:1, or atleast 20:1. Additionally, or alternatively, in an embodiment or incombination with any of the embodiments mentioned herein, the pyrolysisoil may have an n-paraffin to i-paraffin weight ratio of not more than100:1, 7 or not more than 5:1, or not more than 50:1, or not more than40:1, or not more than 30:1. In an embodiment or in combination with anyof the embodiments mentioned herein, the pyrolysis oil may have ann-paraffin to i-paraffin weight ratio in the range of 1:1 to 100:1, 4:1to 100:1, or 15:1 to 100:1.

It should be noted that all of the above-referenced hydrocarbon weightpercentages may be determined using gas chromatography-mass spectrometry(GC-MS).

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may exhibit a density at 15° C. of at least0.6 g/cm3, or at least 0.65 g/cm3, or at least 0.7 g/cm3. Additionally,or alternatively, in an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis oil may exhibit a density at15° C. of not more than 1 g/cm3, or not more than 0.95 g/cm3, or notmore than 0.9 g/cm3, or not more than 0.85 g/cm3. In an embodiment or incombination with any of the embodiments mentioned herein, the pyrolysisoil exhibits a density at 15° C. at a range of 0.6 to 1 g/cm3, 0.65 to0.95 g/cm3, or 0.7 to 0.9 g/cm3.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may exhibit an API gravity at 15° C. of atleast 28, or at least 29, or at least 30, or at least 31, or at least32, or at least 33. Additionally, or alternatively, in an embodiment orin combination with any of the embodiments mentioned herein, thepyrolysis oil may exhibit an API gravity at 15° C. of not more than 50,or not more than 49, or not more than 48, or not more than 47, or notmore than 46, or not more than 45, or not more than 44. In an embodimentor in combination with any of the embodiments mentioned herein, thepyrolysis oil exhibits an API gravity at 15° C. at a range of 28 to 50,29 to 58, or 30 to 44.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a mid-boiling point of at least 75°C., or at least 80° C., or at least 85° C., or at least 90° C., or atleast 95° C., or at least 100° C., or at least 105° C., or at least 110°C., or at least 115° C. The values can be measured according to theprocedures described in either according to ASTM D-2887, or in theworking examples. A mid-boiling point having the stated value aresatisfied if the value is obtained under either method. Additionally, oralternatively, in an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis oil may have a mid-boilingpoint of not more than 250° C., or not more than 245° C., or not morethan 240° C., or not more than 235° C., or not more than 230° C., or notmore than 225° C., or not more than 220° C., or not more than 215° C.,or not more than 210° C., or not more than 205° C., or not more than200° C., or not more than 195° C., or not more than 190° C., or not morethan 185° C., or not more than 180° C., or not more than 175° C., or notmore than 170° C., or not more than 165° C., or not more than 160° C., 1or not more than 55° C., or not more than 150° C., or not more than 145°C., or not more than 140° C., or not more than 135° C., or not more than130° C., or not more than 125° C., or not more than 120° C. The valuescan be measured according to the procedures described in eitheraccording to ASTM D-2887, or in the working examples. A mid-boilingpoint having the stated value are satisfied if the value is obtainedunder either method. In an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis oil may have a mid-boilingpoint in the range of 75 to 250° C., 90 to 225° C., or 115 to 190° C. Asused herein, “mid-boiling point” refers to the median boiling pointtemperature of the pyrolysis oil when 50 weight percent of the pyrolysisoil boils above the mid-boiling point and 50 weight percent boils belowthe mid-boiling point.

In an embodiment or in combination with any of the embodiments mentionedherein, the boiling point range of the pyrolysis oil may be such thatnot more than 10 percent of the pyrolysis oil has a final boiling point(FBP) of 250° C., 280° C., 290° C., 300° C., or 310° C., To determinethe FBP, the procedures described in either according to ASTM D-2887, orin the working examples, can be employed and a FBP having the statedvalues are satisfied if the value is obtained under either method.

Turning to the pyrolysis gas, the pyrolysis gas can have a methanecontent of at least 1, or at least 2, or at least 5, or at least 10, orat least 11, or at least 12, or at least 13, or at least 14, or at least15, or at least 16, or at least 17, or at least 18, or at least 19, orat least 20 weight percent. Additionally, or alternatively, in anembodiment or in combination with any of the embodiments mentionedherein, the pyrolysis gas can have a methane content of not more than50, or not more than 45, or not more than 40, or not more than 35, ornot more than 30, or not more than 25, in each case weight percent. Inan embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis gas can have a methane content in the range of 1to 50 weight percent, 5 to 50 weight percent, or 15 to 45 weightpercent.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis gas can have a C₃ hydrocarbon content of at least1, or at least 2, or at least 3, or at least 4, or at least 5, or atleast 6, or at least 7, or at least 8, or at least 9, or at least 10, orat least 15, or at least 20, or at least 25, in each case weightpercent. Additionally, or alternatively, in an embodiment or incombination with any of the embodiments mentioned herein, the pyrolysisgas can have a C₃hydrocarbon content of not more than 50, or not morethan 45, or not more than 40, or not more than 35, or not more than 30,in each case weight percent. In an embodiment or in combination with anyof the embodiments mentioned herein, the pyrolysis gas can have a C₃hydrocarbon content in the range of 1 to 50 weight percent, 5 to 50weight percent, or 20 to 50 weight percent.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis gas can have a C₄ hydrocarbon content of at least1, or at least 2, or at least 3, or at least 4, or at least 5, or atleast 6, or at least 7, or at least 8, or at least 9, or at least 10, orat least 11, or at least 12, or at least 13, or at least 14, or at least15, or at least 16, or at least 17, or at least 18, or at least 19, orat least 20, in each case weight percent. Additionally, oralternatively, in an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis gas can have a C₄hydrocarbon content of not more than 50, or not more than 45, or notmore than 40, or not more than 35, or not more than 30, or not more than25, in each case weight percent. In an embodiment or in combination withany of the embodiments mentioned herein, the pyrolysis gas can have a C₄hydrocarbon content in the range of 1 to 50 weight percent, 5 to 50weight percent, or 20 to 50 weight percent.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oils of the present invention may be a recyclecontent pyrolysis oil composition (r-pyoil).

Various downstream applications that may utilize the above-disclosedpyrolysis oils and/or the pyrolysis gases are described in greaterdetail below. In an embodiment or in combination with any of theembodiments mentioned herein, the pyrolysis oil may be subjected to oneor more treatment steps prior to being introduced into downstream units,such as a cracking furnace. Examples of suitable treatment steps caninclude, but are not limited to, separation of less desirable components(e.g., nitrogen-containing compounds, oxygenates, and/or olefins andaromatics), distillation to provide specific pyrolysis oil compositions,and preheating.

Turning now to FIG. 3, a schematic depiction of a treatment zone forpyrolysis oil according to an embodiment or in combination with any ofthe embodiments mentioned herein is shown.

As shown in the treatment zone 220 illustrated in FIG. 3, at least aportion of the r-pyoil 252 made from a recycle waste stream 250 in thepyrolysis system 210 may be passed through a treatment zone 220 such as,for example, a separator, which may separate the r-pyoil into a lightpyrolysis oil fraction 254 and a heavy pyrolysis oil fraction 256. Theseparator 220 employed for such a separation can be of any suitabletype, including a single-stage vapor liquid separator or “flash” column,or a multi-stage distillation column. The vessel may or may not includeinternals and may or may not employ a reflux and/or boil-up stream.

In an embodiment or in combination with any of the embodiments mentionedherein, the heavy fraction may have a C₄ to C₇ content or a C₈₊ contentof at least 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80,or 85 weight percent. The light fraction may include at least about 10,15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, or 85 percent ofC₃ and lighter (C³⁻) or C₇ and lighter (C⁷⁻) content. In someembodiments, separator may concentrate desired components into the heavyfraction, such that the heavy fraction may have a C₄ to C₇ content or aC₈₊ content that is at least 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60,65, 70, 7, 80, 85, 90, 95, 100, 105, 110, 115, 120, 125, 130, 135, 140,145, or 150% greater than the C₄ to C₇ content or the C₈₊ content of thepyrolysis oil withdrawn from the pyrolysis zone. As shown in FIG. 3, atleast a portion of the heavy fraction may be sent to the crackingfurnace 230 for cracking as or as part of the r-pyoil composition toform an olefin-containing effluent 258, as discussed in further detailbelow.

In an embodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil is hydrotreated in a treatment zone, while, inother embodiments, the pyrolysis oil is not hydrotreated prior toentering downstream units, such as a cracking furnace. In an embodimentor in combination with any of the embodiments mentioned herein, thepyrolysis oil is not pretreated at all before any downstreamapplications and may be sent directly from the pyrolysis oil source. Thetemperature of the pyrolysis oil exiting the pre-treatment zone can bein the range of 15 to 55° C., 30 to 55° C., 49 to 40° C., 15 to 50° C.,20 to 45° C., or 25 to 40° C.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil may be combined with the non-recycle cracker streamin order to minimize the amount of less desirable compounds present inthe combined cracker feed. For example, when the r-pyoil has aconcentration of less desirable compounds (such as, for example,impurities like oxygen-containing compounds, aromatics, or othersdescribed herein), the r-pyoil may be combined with a cracker feedstockin an amount such that the total concentration of the less desirablecompound in the combined stream is at least 40, 50, 55, 60, 65, 70, 75,80, 85, 90, or 95 percent less than the original content of the compoundin the r-pyoil stream (calculated as the difference between the r-pyoiland combined streams, divided by the r-pyoil content, expressed as apercentage). In some cases, the amount of non-recycle cracker feed tocombine with the r-pyoil stream may be determined by comparing themeasured amount of the one or more less desirable compounds present inthe r-pyoil with a target value for the compound or compounds todetermine a difference and, then, based on that difference, determiningthe amount of non-recycle hydrocarbon to add to the r-pyoil stream. Theamounts of r-pyoil and non-recycle hydrocarbon are within one or moreranges described herein.

At least a portion of the r-ethylene is derived directly or indirectlyfrom the cracking of r-pyoil. The process for obtaining r-olefins fromcracking (r-pyoil) can be as follows and as described in FIG. 4.

Turning now to FIG. 4, a block flow diagram illustrating stepsassociated with the cracking furnace 20 and separation zones 30 of asystem for producing an r-composition obtained from cracking r-pyoil. Asshown in FIG. 4, a feed stream comprising r-pyoil (the r-pyoilcontaining feed stream) may be introduced into a cracking furnace 20,alone or in combination with a non-recycle cracker feed stream. Apyrolysis unit producing r-pyoil can be co-located with the productionfacility. In other embodiments, the r-pyoil can be sourced from a remotepyrolysis unit and transported to the production facility.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil containing feed stream may contain r-pyoil in anamount of at least 1, or at least 5, or at least 10, or at least 15, orat least 20, or at least 25, or at least 30, or at least 35, or at least40, or at least 45, or at least 50, or at least 55, or at least 60, orat least 65, or at least 70, or at least 75, or at least 80, or at least85, or at least 90, or at least 95, or at least 97, or at least 98, orat least 99, or at least or 100, in each case weight percent and/or notmore than 95, or not more than 90, or not more than 85, or not more than80, or not more than 75, or not more than 70, or not more than 65, ornot more than 60, or not more than 55, or not more than 50, or not morethan 45, or not more than 40, or not more than 35, or not more than 30,or not more than 25, or not more than 20, in each case weight percent,based on the total weight of the r-pyoil containing feed stream.

In an embodiment or in combination with any of the embodiments mentionedherein, at least 1, or at least 5, or at least 10, or at least 15, or atleast 20, or at least 25, or at least 30, or at least 35, or at least40, or at least 45, or at least 50, or at least 55, or at least 60, orat least 65, or at least 70, or at least 75, or at least 80, or at least85, or at least 90 or at least 97, or at least 98, or at least 99, or100, in each case weight percent and/or not more than 95, or not morethan 90, or not more than 85, or not more than 80, or not more than 75,or not more than 70, or not more than 65, or not more than 60, or notmore than 55, or not more than 50, or not more than 45, or not more than40, or not more than 35, or not more than 30, or not more than 25, ornot more than 20, or not more than 15 or not more than 10, in each caseweight percent of the r-pyoil is obtained from the pyrolysis of a wastestream. In an embodiment or in combination with any of the embodimentsmentioned herein, at least a portion of the r-pyoil is obtained frompyrolysis of a feedstock comprising plastic waste. Desirably, at least90, or at least 95, or at least 97, or at least 98, or at least 99, orat least or 100, in each case wt. %, of the r-pyoil is obtained frompyrolysis of a feedstock comprising plastic waste, or a feedstockcomprising at least 50 wt. % plastic waste, or a feedstock comprising atleast 80 wt. % plastic waste, or a feedstock comprising at least 90 wt.% plastic waste, or a feedstock comprising at least 95 wt. % plasticwaste.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil can have any one or combination of the compositionalcharacteristics described above with respect to pyrolysis oil.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil may comprise at least 55, or at least 60, or atleast 65, or at least 70, or at least 75, or at least 80, or at least85, or at least 90, or at least 95, in each case weight percent ofC₄-C₃₀ hydrocarbons, and as used herein, hydrocarbons include aliphatic,cycloaliphatic, aromatic, and heterocyclic compounds. In an embodimentor in combination with any of the embodiments mentioned herein, ther-pyoil can predominantly comprise C₅-C₂₅, C₅-C₂₂, or C₅-C₂₀hydrocarbons, or may comprise at least 55, 60, 65, 70, 75, 80, 85, 90,or 95 weight percent of C₅-C₂₅, C₅-C₂₂, or C₅-C₂₀ hydrocarbons.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the r-pyoilcomposition can comprise C₄-C₁₂ aliphatic compounds (branched orunbranched alkanes and alkenes including diolefins, and alicyclics) andC₁₃-C₂₂ aliphatic compounds in a weight ratio of more than 1:1, or atleast 1.25:1, or at least 1.5:1, or at least 2:1, or at least 2.5:1, orat least 3:1, or at least 4:1, or at least 5:1, or at least 6:1, or atleast 7:1, 10:1, 20:1, or at least 40:1, each by weight and based on theweight of the r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the r-pyoilcomposition can comprise C₁₃-C₂₂ aliphatic compounds (branched orunbranched alkanes and alkenes including diolefins, and alicyclics) andC₄-C₁₂ aliphatic compounds in a weight ratio of more than 1:1, or atleast 1.25:1, or at least 1.5:1, or at least 2:1, or at least 2.5:1, orat least 3:1, or at least 4:1, or at least 5:1, or at least 6:1, or atleast 7:1, 10:1, 20:1, or at least 40:1, each by weight and based on theweight of the r-pyoil.

In an embodiment, the two aliphatic hydrocarbons (branched or unbranchedalkanes and alkenes, and alicyclics) having the highest concentration inthe r-pyoil are in a range of C₅-C₁₈, or C₅-C₁₆, or C₅-C₁₄, or C₅-C₁₀,or C₅-C₈, inclusive.

The r-pyoil includes one or more of paraffins, naphthenes or cyclicaliphatic hydrocarbons, aromatics, aromatic containing compounds,olefins, oxygenated compounds and polymers, heteroatom compounds orpolymers, and other compounds or polymers.

For example, in an embodiment or in combination with any of theembodiments mentioned herein, the r-pyoil may comprise at least 5, or atleast 10, or at least 15, or at least 20, or at least 25, or at least30, or at least 35, or at least 40, or at least 45, or at least 50, orat least 55, or at least 60, or at least 65, or at least 70, or at least75, or at least 80, or at least 85, or at least 90, or at least 95, ineach case weight percent and/or not more than 99, or not more than 97,or not more than 95, or not more than 93, or not more than 90, or notmore than 87, or not more than 85, or not more than 83, or not more than80, or not more than 78, or not more than 75, or not more than 70, ornot more than 65, or not more than 60, or not more than 55, or not morethan 50, or not more than 45, or not more than 40, or not more than 35,or not more than 30, or not more than 25, or not more than 20, or notmore than 15, in each case weight percent of paraffins (or linear orbranched alkanes), based on the total weight of the r-pyoil. In anembodiment or in combination with any of the embodiments mentionedherein, the pyrolysis oil may have a paraffin content in the range of 25to 90, 35 to 90, or 40 to 80, or 40-70, or 40-65 weight percent, or5-50, or 5 to 40, or 5 to 35, or 10- to 35, or 10 to 30, or 5 to 25, or5 to 20, in each case as wt. % based on the weight of the r-pyoilcomposition.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil can include naphthenes or cyclic aliphatichydrocarbons in amount of zero, or at least 1, or at least 2, or atleast 5, or at least 8, or at least 10, or at least 15, or at least 20,in each case weight percent and/or not more than 50, or not more than45, or not more than 40, or not more than 35, or not more than 30, ornot more than 25, or not more than 20, or not more than 15, or not morethan 10, or not more than 5, or not more than 2, or not more than 1, ornot more than 0.5, or no detectable amount, in each case weight percent.In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil may have a naphthene content of not more than 5, ornot more than 2, or not more than 1 wt. %, or no detectable amount, ornaphthenes. Examples of ranges for the amount of naphthenes (or cyclicaliphatic hydrocarbons) contained in the r-pyoil is from 0-35, or 0-30,or 0-25, or 2-20, or 2-15, or 2-10, or 1-10, in each case as wt. % basedon the weight of the r-pyoil composition.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil may have a paraffin to olefin weight ratio of atleast 0.2:1, or at least 0.3:1, or at least 0.4:1, or at least 0.5:1, orat least 0.6:1, or at least 0.7:1, or at least 0.8:1, or at least 0.9:1,or at least 1:1. Additionally, or alternatively, in an embodiment or incombination with any of the embodiments mentioned herein, the r-pyoilmay have a paraffin to olefin weight ratio not more than 3:1, or notmore than 2.5:1, or not more than 2:1, or not more than 1.5:1, or notmore than 1.4:1, or not more than 1.3:1. In an embodiment or incombination with any of the embodiments mentioned herein, the r-pyoilmay have a paraffin to olefin weight ratio in the range of 0.2:1 to 5:1,or 1:1 to 4.5:1, or 1.5:1 to 5:1, or 1.5:1:4.5:1, or 0.2:1 to 4:1, or0.2:1 to 3:1, 0.5:1 to 3:1, or 1:1 to 3:1.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil may have an n-paraffin to i-paraffin weight ratio ofat least 0.001:1, or at least 0.1:1, or at least 0.2:1, or at least0.5:1, or at least 1:1, or at least 2:1, or at least 3:1, or at least4:1, or at least 5:1, or at least 6:1, or at least 7:1, or at least 8:1,or at least 9:1, or at least 10:1, or at least 15:1, or at least 20:1.Additionally, or alternatively, in an embodiment or in combination withany of the embodiments mentioned herein, the r-pyoil may have ann-paraffin to i-paraffin weight ratio of not more than 100:1, or notmore than 50:1, or not more than 40:1, or not more than 30:1. In anembodiment or in combination with any of the embodiments mentionedherein, the r-pyoil may have an n-paraffin to i-paraffin weight ratio inthe range of 1:1 to 100:1, 4:1 to 100:1, or 15:1 to 100:1.

In an embodiment, the r-pyoil comprises not more than 30, or not morethan 25, or not more than 20, or not more than 15, or not more than 10,or not more than 8, or not more than 5, or not more than 2, or not morethan 1, in each case weight percent of aromatics, based on the totalweight of the r-pyoil. As used herein, the term “aromatics” refers tothe total amount (in weight) of benzene, toluene, xylene, and styrene.The r-pyoil may include at least 1, or at least 2, or at least 5, or atleast 8, or at least 10, in each case weight percent of aromatics, basedon the total weight of the r-pyoil.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil can include aromatic containing compounds in anamount of not more than 30, or not more than 25, or not more than 20, ornot more than 15, or not more than 10, or not more than 8, or not morethan 5, or not more than 2, or not more than 1, in each case weight, ornot detectable, based on the total weight of the r-pyoil. Aromaticcontaining compounds includes the above-mentioned aromatics and anycompounds containing an aromatic moiety, such as terephthalate residuesand fused ring aromatics such as the naphthalenes andtetrahydronaphthalene.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil can include olefins in amount of at least 1, or atleast 2, or at least 5, or at least 8, or at least 10, or at least 15,or at least 20, or at least 30, or at least 40, or at least 45, or atleast 50, or at least 55, or at least 60, or at least or at least 65, ineach case weight percent olefins and/or not more than 85, or not morethan 80, or not more than 75, or not more than 70, or not more than 65,or not more than 60, or not more than 55, or not more than 50, or notmore than 45, or not more than 40, or not more than 35, or not more than30, or not more than 25, or not more than 20, or not more than 15, ornot more than 10, in each case weight percent, based on the weight of ar-pyoil. Olefins include mono- and di-olefins. Examples of suitableranges include olefins present in an amount ranging from 5 to 45, or10-35, or 15 to 30, or 40-85, or 45-85, or 50-85, or 55-85, or 60-85, or65-85, or 40-80, or 45-80, or 50-80, or 55-80, or 60-80, or 65-80,45-80, or 50-80, or 55-80, or 60-80, or 65-80, or 40-75, or 45-75, or50-75, or 55-75, or 60-75, or 65-75, or 40-70, or 45-70, or 50-70, or55-70, or 60-70, or 65-70, or 40-65, or 45-65, or 50-65, or 55-65, ineach case as wt. % based on the weight of the r-pyoil.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil can include oxygenated compounds or polymers inamount of zero or at least 0.01, or at least 0.1, or at least 1, or atleast 2, or at least 5, in each case weight percent and/or not more than20, or not more than 15, or not more than 10, or not more than 8, or notmore than 6, or not more than 5, or not more than 3, or not more than 2,in each case weight percent oxygenated compounds or polymers, based onthe weight of a r-pyoil. Oxygenated compounds and polymers are thosecontaining an oxygen atom. Examples of suitable ranges includeoxygenated compounds present in an amount ranging from 0-20, or 0-15, or0-10, or 0.01-10, or 1-10, or 2-10, or 0.01-8, or 0.1-6, or 1-6, or0.01-5, in each case as wt. % based on the weight of the r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the amount ofoxygen atoms in the r-pyoil can be not more than 10, or not more than 8,or not more than 5, or not more than 4, or not more than 3, or not morethan 2.75, or not more than 2.5, or not more than 2.25, or not more than2, or not more than 1.75, or not more than 1.5, or not more than 1.25,or not more than 1, or not more than 0.75, or not more than 0.5, or notmore than 0.25, or not more than 0.1, or not more than 0.05, in eachcase wt. %, based on the weight of the r-pyoil. Examples of the amountof oxygen in the r-pyoil can be from 0-8, or 0-5, or 0-3, or 0-2.5 or0-2, or 0.001-5, or 0.001-4, or 0.001-3, or 0.001-2.75, or 0.001-2.5, or0.001-2, or 0.001-1.5, or 0.001-1, or 0.001-0.5, or 0.001-0.1, in eachcase as wt. % based on the weight of the r-pyoil.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil can include heteroatom compounds or polymers inamount of at least 1, or at least 2, or at least 5, or at least 8, or atleast 10, or at least 15, or at least 20, in each case weight percentand/or not more than 25, or not more than 20, or not more than 15, ornot more than 10, or not more than 8, or not more than 6, or not morethan 5, or not more than 3, or not more than 2, in each case weightpercent, based on the weight of a r-pyoil. A heterocompound or polymeris defined in this paragraph as any compound or polymer containingnitrogen, sulfur, or phosphorus. Any other atom is not regarded as aheteroatom for purposes of determining the quantity of heteroatoms,heterocompounds, or heteropolymers present in the r-pyoil. The r-pyoilcan contain heteroatoms present in an amount of not more than 5, or notmore than 4, or not more than 3, or not more than 2.75, or not more than2.5, or not more than 2.25, or not more than 2, or not more than 1.75,or not more than 1.5, or not more than 1.25, or not more than 1, or notmore than 0.75, or not more than 0.5, or not more than 0.25, or not morethan 0.1, or not more than 0.075, or not more than 0.05, or not morethan 0.03, or not more than 0.02, or not more than 0.01, or not morethan 0.008, or not more than 0.006, or not more than 0.005, or not morethan 0.003, or not more than 0.002, in each case wt. %, based on theweight of the r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein, thesolubility of water in the r-pyoil at 1 atm and 25° C. is less than 2wt. %, water, or not more than 1.5, or not more than 1, or not more than0.5, or not more than 0.1, or not more than 0.075, or not more than0.05, or not more than 0.025, or not more than 0.01, or not more than0.005, in each case wt. % water based on the weight of the r-pyoil.Desirably, the solubility of water in the r-pyoil is not more than 0.1wt. % based on the weight of the r-pyoil. In an embodiment or incombination with any embodiment mentioned herein or in combination withany of the embodiments mentioned herein, the r-pyoil contains not morethan 2 wt. %, water, or not more than 1.5, or not more than 1, or notmore than 0.5, desirably or not more than 0.1, or not more than 0.075,or not more than 0.05, or not more than 0.025, or not more than 0.01, ornot more than 0.005, in each case wt. % water based on the weight of ther-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein, thesolids content in the r-pyoil does not exceed 1, or is not more than0.75, or not more than 0.5, or not more than 0.25, or not more than 0.2,or not more than 0.15, or not more than 0.1, or not more than 0.05, ornot more than 0.025, or not more than 0.01, or not more than 0.005, ordoes not exceed 0.001, in each case wt. % solids based on the weight ofthe r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein thesulfur content of the r-pyoil does not exceed 2.5 wt. %, or is not morethan 2, or not more than 1.75, or not more than 1.5, or not more than1.25, or not more than 1, or not more than 0.75, or not more than 0.5,or not more than 0.25, or not more than 0.1, or not more than 0.05,desirably or not more than 0.03, or not more than 0.02, or not more than0.01, or not more than 0.008, or not more than 0.006, or not more than0.004, or not more than 0.002, or is not more than 0.001, in each casewt. % based on the weight of the r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein, ther-pyoil can have the following compositional content:

carbon atom content of at least 75 wt. %, or at least or at least 77, orat least 80, or at least 82, or at least 85, in each case wt. %, and/orup to 90, or up to 88, or not more than 86, or not more than 85, or notmore than 83, or not more than 82, or not more than 80, or not more than77, or not more than 75, or not more than 73, or not more than 70, ornot more than 68, or not more than 65, or not more than 63, or up to 60,in each case wt. %, desirably at least 82% and up to 93%, and/orhydrogen atom content of at least 10 wt. %, or at least 13, or at least14, or at least 15, or at least 16, or at least 17, or at least 18, ornot more than 19, or not more than 18, or not more than 17, or not morethan 16, or not more than 15, or not more than 14, or not more than 13,or up to 11, in each case wt. %, an oxygen atom content not to exceed10, or not more than 8, or not more than 5, or not more than 4, or notmore than 3, or not more than 2.75, or not more than 2.5, or not morethan 2.25, or not more than 2, or not more than 1.75, or not more than1.5, or not more than 1.25, or not more than 1, or not more than 0.75,or not more than 0.5, or not more than 0.25, or not more than 0.1, ornot more than 0.05, in each case wt. %, in each case based on the weightof the r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the amount ofhydrogen atoms in the r-pyoil can be in a range of from 10-20, or 10-18,or 11-17, or 12-16 or 13-16, or 13-15, or 12-15, in each case as wt. %based on the weight of the r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein, themetal content of the r-pyoil is desirably low, for example, not morethan 2 wt. %, or not more than 1, or not more than 0.75, or not morethan 0.5, or not more than 0.25, or not more than 0.2, or not more than0.15, or not more than 0.1, or not more than 0.05, in each case wt. %based on the weight of the r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein, thealkali metal and alkaline earth metal or mineral content of the r-pyoilis desirably low, for example, not more than 2 wt. %, or not more than1, or not more than 0.75, or not more than 0.5, or not more than 0.25,or not more than 0.2, or not more than 0.15, or not more than 0.1, ornot more than 0.05, in each case wt. % based on the weight of ther-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein, theweight ratio of paraffin to naphthene in the r-pyoil can be at least1:1, or at least 1.5:1, or at least 2:1, or at least 2.2:1, or at least2.5:1, or at least 2.7:1, or at least 3:1, or at least 3.3:1, or atleast 3.5:1, or at least 3.75:1, or at least 4:1, or at least 4.25:1, orat least 4.5:1, or at least 4.75:1, or at least 5:1, or at least 6:1, orat least 7:1, or at least 8:1, or at least 9:1, or at least 10:1, or atleast 13:1, or at least 15:1, or at least 17:1, based on the weight ofthe r-pyoil.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein, theweight ratio of paraffin and naphthene combined to aromatics can be atleast 1:1, or at least 1.5:1, or at least 2:1, or at least 2.5:1, or atleast 2.7:1, or at least 3:1, or at least 3.3:1, or at least 3.5:1, orat least 3.75:1, or at least 4:1, or at least 4.5:1, or at least 5:1, orat least 7:1, or at least 10:1, or at least 15:1, or at least 20:1, orat least 25:1, or at least 30:1, or at least 35:1, or at least 40:1,based on the weight of the r-pyoil. In an embodiment or in combinationwith any embodiment mentioned herein or in combination with any of thementioned embodiments, the ratio of paraffin and naphthene combined toaromatics in the r-pyoil can be in a range of from 50:1-1:1, or40:1-1:1, or 30:1-1:1, or 20:1-1:1, or 30:1-3:1, or 20:1-1:1, or20:1-5:1, or 50:1-5:1, or 30:1-5:1, or 1:1-7:1, or 1:1-5:1, 1:1-4:1, or1:1-3:1.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil may have a boiling point curve defined by one ormore of its 10%, its 50%, and its 90% boiling points, as defined below.As used herein, “boiling point” refers to the boiling point of acomposition as determined by ASTM D2887 or according to the proceduredescribed in the working examples. A boiling point having the statedvalues are satisfied if the value is obtained under either method.Additionally, as used herein, an “x % boiling point,” refers to aboiling point at which x percent by weight of the composition boils pereither of these methods.

As used throughout, an x % boiling at a stated temperature means atleast x % of the composition boils at the stated temperature. In anembodiment or in combination with any of the embodiments mentionedherein, the 90% boiling point of the cracker feed stream or compositioncan be not more than 350, or not more than 325, or not more than 300, ornot more than 295, or not more than 290, or not more than 285, or notmore than 280, or not more than 275, or not more than 270, or not morethan 265, or not more than 260, or not more than 255, or not more than250, or not more than 245, or not more than 240, or not more than 235,or not more than 230, or not more than 225, or not more than 220, or notmore than 215, not more than 200, not more than 190, not more than 180,not more than 170, not more than 160, not more than 150, or not morethan 140, in each case ° C. and/or at least 200, or at least 205, or atleast 210, or at least 215, or at least 220, or at least 225, or atleast 230, in each case ° C. and/or not more than 25, 20, 15, 10, 5, or2 weight percent of the r-pyoil may have a boiling point of 300° C. orhigher.

Referring again to FIG. 3, the r-pyoil may be introduced into a crackingfurnace or coil or tube alone (e.g., in a stream comprising at least 85,or at least 90, or at least 95, or at least 99, or 100, in each case wt.% percent pyrolysis oil based on the weight of the cracker feed stream),or combined with one or more non-recycle cracker feed streams. Whenintroduced into a cracker furnace, coil, or tube with a non-recyclecracker feed stream, the r-pyoil may be present in an amount of at least1, or at least 2, or at least 5, or at least 8, or at least 10, or atleast 12, or at least 15, or at least 20, or at least 25, or at least30, in each case wt. % and/or not more than 40, or not more than 35, ornot more than 30, or not more than 25, or not more than 20, or not morethan 15, or not more than 10, or not more than 8, or not more than 5, ornot more than 2, in each case weight percent based on the total weightof the combined stream. Thus, the non-recycle cracker feed stream orcomposition may be present in the combined stream in an amount of atleast 20, or at least 25, or at least 30, or at least 35, or at least40, or at least 45, or at least 50, or at least 55, or at least 60, orat least 65, or at least 70, or at least 75, or at least 80, or at least85, or at least 90, in each case weight percent and/or not more than 99,or not more than 95, or not more than 90, or not more than 85, or notmore than 80, or not more than 75, or not more than 70, or not more than65, or not more than 60, or not more than 55, or not more than 50, ornot more than 45, or not more than 40, in each case weight percent basedon the total weight of the combined stream. Unless otherwise notedherein, the properties of the cracker feed stream as described belowapply either to the non-recycle cracker feed stream prior to (or absent)combination with the stream comprising r-pyoil, as well as to a combinedcracker stream including both a non-recycle cracker feed and a r-pyoilfeed.

In an embodiment or in combination with any of the embodiments mentionedherein, the cracker feed stream may comprise a predominantly C₂-C₄hydrocarbon containing composition, or a predominantly C₅-C₂₂hydrocarboncontaining composition. As used herein, the term “predominantly C₂-C₄hydrocarbon,” refers to a stream or composition containing at least 50weight percent of C₂-C₄ hydrocarbon components. Examples of specifictypes of C₂-C₄ hydrocarbon streams or compositions include propane,ethane, butane, and LPG. In an embodiment or in combination with any ofthe embodiments mentioned herein, the cracker feed may comprise at least50, or at least 55, or at least 60, or at least 65, or at least 70, orat least 75, or at least 80, or at least 85, or at least 90, or at least95, in each case wt. % based on the total weight of the feed, and/or notmore than 100, or not more than 99, or not more than 95, or not morethan 92, or not more than 90, or not more than 85, or not more than 80,or not more than 75, or not more than 70, or not more than 65, or notmore than 60, in each case weight percent C₂-C₄ hydrocarbons or linearalkanes, based on the total weight of the feed. The cracker feed cancomprise predominantly propane, predominantly ethane, predominantlybutane, or a combination of two or more of these components. Thesecomponents may be non-recycle components. The cracker feed can comprisepredominantly propane, or at least 50 mole % propane, or at least 80mole % propane, or at least 90 mole % propane, or at least 93 mole %propane, or at least 95 mole % propane (inclusive of any recycle streamscombined with virgin feed). The cracker feed can comprise HD5 qualitypropane as a virgin or fresh feed. The cracker can comprise at more than50 mole % ethane, or at least 80 mole % ethane, or at least 90 mole %ethane, or at least 95 mole % ethane. These components may benon-recycle components.

In an embodiment or in combination with any of the embodiments mentionedherein, the cracker feed stream may comprise a predominantly C₅-C₂₂hydrocarbon containing composition. As used herein, “predominantlyC₅-C₂₂ hydrocarbon” refers to a stream or composition comprising atleast 50 weight percent of C₅-C₂₂ hydrocarbon components. Examplesinclude gasoline, naphtha, middle distillates, diesel, kerosene. In anembodiment or in combination with any of the embodiments mentionedherein, the cracker feed stream or composition may comprise at least 20,or at least 25, or at least 30, or at least 35, or at least 40, or atleast 45, or at least 50, or at least 55, or at least 60, or at least65, or at least 70, or at least 75, or at least 80, or at least 85, orat least 90, or at least 95, in each case wt. % and/or not more than100, or not more than 99, or not more than 95, or not more than 92, ornot more than 90, or not more than 85, or not more than 80, or not morethan 75, or not more than 70, or not more than 65, or not more than 60,in each case weight percent C₅-C₂₂, or C₅-C₂₀ hydrocarbons, based on thetotal weight of the stream or composition. In an embodiment or incombination with any of the embodiments mentioned herein, the crackerfeed may have a C15 and heavier (C15+) content of at least 0.5, or atleast 1, or at least 2, or at least 5, in each case weight percentand/or not more than 40, or not more than 35, or not more than 30, ornot more than 25, or not more than 20, or not more than 18, or not morethan 15, or not more than 12, or not more than 10, or not more than 5,or not more than 3, in each case weight percent, based on the totalweight of the feed.

The cracker feed may have a boiling point curve defined by one or moreof its 10%, its 50%, and its 90% boiling points, the boiling point beingobtained by the methods described above Additionally, as used herein, an“x % boiling point,” refers to a boiling point at which x percent byweight of the composition boils per the methods described above. In anembodiment or in combination with any of the embodiments mentionedherein, the 90% boiling point of the cracker feed stream or compositioncan be not more than 360, or not more than 355, or not more than 350, ornot more than 345, or not more than 340, or not more than 335, or notmore than 330, or not more than 325, or not more than 320, or not morethan 315, or not more than 300, or not more than 295, or not more than290, or not more than 285, or not more than 280, or not more than 275,or not more than 270, or not more than 265, or not more than 260, or notmore than 255, or not more than 250, or not more than 245, or not morethan 240, or not more than 235, or not more than 230, or not more than225, or not more than 220, or not more than 215, in each case ° C.and/or at least 200, or at least 205, or at least 210, or at least 215,or at least 220, or at least 225, or at least 230, in each case ° C.

In an embodiment or in combination with any of the embodiments mentionedherein, the 10% boiling point of the cracker feed stream or compositioncan be at least 40, at least 50, at least 60, at least 70, at least 80,at least 90, at least 100, at least 110, at least 120, at least 130, atleast 140, at least 150, or at least 155, in each case ° C. and/or notmore than 250, not more than 240, not more than 230, not more than 220,not more than 210, not more than 200, not more than 190, not more than180, or not more than 170 in each case ° C.

In an embodiment or in combination with any of the embodiments mentionedherein, the 50% boiling point of the cracker feed stream or compositioncan be at least 60, at least 65, at least 70, at least 75, at least 80,at least 85, at least 90, at least 95, at least 100, at least 110, atleast 120, at least 130, at least 140, at least 150, at least 160, atleast 170, at least 180, at least 190, at least 200, at least 210, atleast 220, or at least 230, in each case ° C., and/or not more than 300,not more than 290, not more than 280, not more than 270, not more than260, not more than 250, not more than 240, not more than 230, not morethan 220, not more than 210, not more than 200, not more than 190, notmore than 180, not more than 170, not more than 160, not more than 150,or not more than 145° C. The 50% boiling point of the cracker feedstream or composition can be in the range of 65 to 160, 70 to 150, 80 to145, 85 to 140, 85 to 230, 90 to 220, 95 to 200, 100 to 190, 110 to 180,200 to 300, 210 to 290, 220 to 280, 230 to 270, in each case in ° C.

In an embodiment or in combination with any of the embodiments mentionedherein, the 90% boiling point of the cracker feedstock or stream orcomposition can be at least 350° C., the 10% boiling point can be atleast 60° C.; and the 50% boiling point can be in the range of from 95°C. to 200° C. In an embodiment or in combination with any of theembodiments mentioned herein, the 90% boiling point of the crackerfeedstock or stream or composition can be at least 150° C., the 10%boiling point can be at least 60° C., and the 50% boiling point can bein the range of from 80 to 145° C. In an embodiment or in combinationwith any of the embodiments mentioned herein, the cracker feedstock orstream has a 90% boiling point of at least 350° C., a 10% boiling pointof at least 150° C., and a 50% boiling point in the range of from 220 to280° C.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the embodiments mentioned herein, ther-pyoil is cracked in a gas furnace. A gas furnace is a furnace havingat least one coil which receives (or operated to receive), at the inletof the coil at the entrance to the convection zone, a predominatelyvapor-phase feed (more than 50% of the weight of the feed is vapor)(“gas coil”). In an embodiment or in combination with any embodimentmentioned herein or in combination with any of the mentionedembodiments, the gas coil can receive a predominately C₂-C₄ feedstock,or a predominately a C₂-C₃ feedstock to the inlet of the coil in theconvection section, or alternatively, having at least one coil receivingmore than 50 wt. % ethane and/or more than 50% propane and/or more than50% LPG, or in any one of these cases at least 60 wt. %, or at least 70wt. %, or at least 80 wt. %, based on the weight of the cracker feed tothe coil, or alternatively based on the weight of the cracker feed tothe convection zone. The gas furnace may have more than one gas coil. Inan embodiment or in combination with any embodiment mentioned herein orin combination with any of the mentioned embodiments, at least 25% ofthe coils, or at least 50% of the coils, or at least 60% of the coils,or all the coils in the convection zone or within a convection box ofthe furnace are gas coils. In an embodiment or in combination with anyembodiment mentioned herein or in combination with any of the mentionedembodiments, the gas coil receives, at the inlet of the coil at theentrance to the convection zone, a vapor-phase feed in which at least 60wt. %, or at least 70 wt. %, or at least 80 wt. %, or at least 90 wt. %,or at least 95 wt. %, or at least 97 wt. %, or at least 98 wt. %, or atleast 99 wt. %, or at least 99.5 wt. %, or at least 99.9 wt. % of feedis vapor.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the r-pyoil iscracked in a split furnace. A split furnace is a type of gas furnace. Asplit furnace contains at least one gas coil and at least one liquidcoil within the same furnace, or within the same convection zone, orwithin the same convection box. A liquid coil is a coil which receives,at the inlet of coil at the entrance to the convection zone, apredominately liquid phase feed (more than 50% of the weight of the feedis liquid) (“liquid coil”). In an embodiment or in combination with anyembodiment mentioned herein or in combination with any of the mentionedembodiments, the liquid coil can receive a predominately C₅₊ feedstockto the inlet of the coil at the entrance of the convection section(“liquid coil”). In an embodiment or in combination with any embodimentmentioned herein or in combination with any of the mentionedembodiments, the liquid coil can receive a predominately C₆-C₂₂feedstock, or a predominately a C₇-C₁₆ feedstock to the inlet of thecoil in the convection section, or alternatively, having at least onecoil receiving more than 50 wt. % naphtha, and/or more than 50% naturalgasoline, and/or more than 50% diesel, and/or more than JP-4, and/ormore than 50% Stoddard Solvent, and/or more than 50% kerosene, and/ormore than 50% fresh creosote, and/or more than 50% JP-8 or Jet-A, and/ormore than 50% heating oil, and/or more than 50% heavy fuel oil, and/ormore than 50% bunker C, and/or more than 50% lubricating oil, or in anyone of these cases at least 60 wt. %, or at least 70 wt. %, or at least80 wt. %, or at least 90 wt. %, or at least 95 wt. %, or at least 98 wt.%, or at least 99 wt. %, based on the weight of the cracker feed to theliquid coil, or alternatively based on the weight of the cracker feed tothe convection zone. In an embodiment or in combination with anyembodiment mentioned herein or in combination with any of the mentionedembodiments, at least one coil and not more than 75% of the coils, ornot more than 50% of the coils, or not more than at least 40% of thecoils in the convection zone or within a convection box of the furnaceare liquid coils. In an embodiment or in combination with any embodimentmentioned herein or in combination with any of the mentionedembodiments, the liquid coil receives, at the inlet of the coil at theentrance to the convection zone, a liquid-phase feed in which at least60 wt. %, or at least 70 wt. %, or at least 80 wt. %, or at least 90 wt.%, or at least 95 wt. %, or at least 97 wt. %, or at least 98 wt. %, orat least 99 wt. %, or at least 99.5 wt. %, or at least 99.9 wt. % offeed is liquid.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the r-pyoil iscracked in a thermal gas cracker.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the r-pyoil iscracked in a thermal steam gas cracker in the presence of steam. Steamcracking refers to the high-temperature cracking (decomposition) ofhydrocarbons in the presence of steam.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, ther-composition is derived directly or indirectly from cracking r-pyoil ina gas furnace. The coils in the gas furnace can consist entirely of gascoils or the gas furnace can be a split furnace.

When the r-pyoil containing feed stream is combined with the non-recyclecracker feed, such a combination may occur upstream of, or within, thecracking furnace or within a single coil or tube. Alternatively, ther-pyoil containing feed stream and non-recycle cracker feed may beintroduced separately into the furnace, and may pass through a portion,or all, of the furnace simultaneously while being isolated from oneanother by feeding into separate tubes within the same furnace (e.g., asplit furnace). Ways of introducing the r-pyoil containing feed streamand the non-recycle cracker feed into the cracking furnace according toan embodiment or in combination with any of the embodiments mentionedherein are described in further detail below.

Turning now to FIG. 5, a schematic diagram of a cracker furnace suitablefor use in an embodiment or in combination with any of the embodimentsmentioned herein is shown.

In one embodiment or in combination of any of the mentioned embodiments,there is provided a method for making one or more olefins including:

(a) feeding a first cracker feed comprising a recycle content pyrolysisoil composition (r-pyoil) to a cracker furnace;

(b) feeding a second cracker feed into said cracker furnace, whereinsaid second cracker feed comprises none of said r-pyoil or less of saidr-pyoil, by weight, than said first cracker feed stream; and

(c) cracking said first and said second cracker feeds in respectivefirst and second tubes to form an olefin-containing effluent stream.

The r-pyoil can be combined with a cracker stream to make a combinedcracker stream, or as noted above, a first cracker stream. The firstcracker stream can be 100% r-pyoil or a combination of a non-recyclecracker stream and r-pyoil. The feeding of step (a) and/or step (b) canbe performed upstream of the convection zone or within the convectionzone. The r-pyoil can be combined with a non-recycle cracker stream toform a combined or first cracker stream and fed to the inlet of aconvection zone, or alternatively the r-pyoil can be separately fed tothe inlet of a coil or distributor along with a non-recycle crackerstream to form a first cracker stream at the inlet of the convectionzone, or the r-pyoil can be fed downstream of the inlet of theconvection zone into a tube containing non-recycle cracker feed, butbefore a crossover, to make a first cracker stream or combined crackerstream in a tube or coil. Any of these methods includes feeding thefirst cracker stream to the furnace.

The amount of r-pyoil added to the non-recycle cracker stream to makethe first cracker stream or combined cracker stream can be as describedabove; e.g. in an amount of at least 1, 5, 10, 15, 20, 25, 30, 35, 40,45, 50, 55, 60, 65, 70, 75, 80, 85, 90, or 95, in each case weightpercent and/or not more than 95, 90, 85, 80, 75, 70, 65, 60, 55, 60, 55,50, 45, 40, 35, 30, 25, 20, 15, or 1, in each case weight percent, basedon the total weight of the first cracker feed or combined cracker feed(either as introduced into the tube or within the tube as noted above).Further examples include 5-50, 5-40, 5-35, 5-30, 5-25, 5-20, or 5-15 wt.%.

The first cracker stream is cracked in a first coil or tube. The secondcracker stream is cracked in a second coil or tube. Both the first andsecond cracker streams and the first and second coils or tubes can bewithin the same cracker furnace.

The second cracker stream can have none of the r-pyoil or less of saidr-pyoil, by weight, than the first cracker feed stream. Also, the secondcracker stream can contain only non-recycle cracker feed in the secondcoil or tube. The second cracker feed stream can be predominantly C₂ toC₄, or hydrocarbons (e.g. non-recycle content), or ethane, propane, orbutane, in each case in amounts of at least 55, 60, 65, 70, 75, 80, 85,or at least 90 weight percent based on the second cracker feed within asecond coil or tube. If r-pyoil is included in the second cracker feed,the amount of such r-pyoil can be at least 10% less, 20, 30, 40, 50, 60,70, 80, 90, 95, 97, or 99% less by weight than the amount of r-pyoil inthe first cracker feed.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, although notshown, a vaporizer can be provided to vaporize a condensed feedstock ofC₂-C₅ hydrocarbons 350 to ensure that the feed to the inlet of the coilsin the convection box 312, or the inlet of the convection zone 310, is apredominately vapor phase feed.

The cracking furnace shown in FIG. 5 includes a convection section orzone 310, a radiant section or zone 320, and a cross-over section orzone 330 located between the convection and radiant sections 310 and320. The convection section 310 is the portion of the furnace 300 thatreceives heat from hot flue gases and includes a bank of tubes or coils324 through which a cracker stream 350 passes. In the convection section310, the cracker stream 350 is heated by convection from the hot fluegasses passing therethrough. The radiant section 320 is the section ofthe furnace 300 into which heat is transferred into the heater tubesprimarily by radiation from the high-temperature gas. The radiantsection 320 also includes a plurality of burners 326 for introducingheat into the lower portion of the furnace. The furnace includes a firebox 322 which surrounds and houses the tubes within the radiant section320 and into which the burners are oriented. The cross-over section 330includes piping for connecting the convection 310 and radiant sections320 and may transfer the heated cracker stream internally or externallyfrom one section to the other within the furnace 300.

As hot combustion gases ascend upwardly through the furnace stack, thegases may pass through the convection section 310, wherein at least aportion of the waste heat may be recovered and used to heat the crackerstream passing through the convection section 310. In an embodiment orin combination with any of the embodiments mentioned herein, thecracking furnace 300 may have a single convection (preheat) section 310and a single radiant 320 section, while, in other embodiments, thefurnace may include two or more radiant sections sharing a commonconvection section. At least one induced draft (I.D.) fan 316 near thestack may control the flow of hot flue gas and heating profile throughthe furnace, and one or more heat exchangers 340 may be used to cool thefurnace effluent 370. In an embodiment or in combination with any of theembodiments mentioned herein (not shown), a liquid quench may be used inaddition to, or alternatively with, the exchanger (e.g., transfer lineheat exchanger or TLE) shown in FIG. 5, for cooling the crackedolefin-containing effluent.

The furnace 300 also includes at least one furnace coil 324 throughwhich the cracker streams pass through the furnace. The furnace coils324 may be formed of any material inert to the cracker stream andsuitable for withstanding high temperatures and thermal stresses withinthe furnace. The coils may have any suitable shape and can, for example,have a circular or oval cross-sectional shape.

The coils in the convection section 310, or tubes within the coil, mayhave a diameter of at least 1, or at least 1.5, or at least 2, or atleast 2.5, or at least 3, or at least 3.5, or at least 4, or at least4.5, or at least 5, or at least 5.5, or at least 6, or at least 6.5, orat least 7, or at least 7.5, or at least 8, or at least 8.5, or at least9, or at least 9.5, or at least 10, or at least 10.5, in each case cmand/or not more than 12, or not more than 11.5, or not more than 11, 1or not more than 0.5, or not more than 10, or not more than 9.5, or notmore than 9, or not more than 8.5, or not more than 8, or not more than7.5, or not more than 7, or not more than 6.5, in each case cm. All or aportion of one or more coils can be substantially straight, or one ormore of the coils may include a helical, twisted, or spiral segment. Oneor more of the coils may also have a U-tube or split U-tube design. Inan embodiment or in combination with any of the embodiments mentionedherein, the interior of the tubes may be smooth or substantially smooth,or a portion (or all) may be roughened in order to minimize coking.Alternatively, or in addition, the inner portion of the tube may includeinserts or fins and/or surface metal additives to prevent coke build up.

In an embodiment or in combination with any of the embodiments mentionedherein, all or a portion of the furnace coil or coils 324 passingthrough in the convection section 310 may be oriented horizontally,while all, or at least a portion of, the portion of the furnace coilpassing through the radiant section 322 may be oriented vertically. Inan embodiment or in combination with any of the embodiments mentionedherein, a single furnace coil may run through both the convection andradiant section. Alternatively, at least one coil may split into two ormore tubes at one or more points within the furnace, so that crackerstream may pass along multiple paths in parallel. For example, thecracker stream (including r-pyoil) 350 may be introduced into multiplecoil inlets in the convection zone 310, or into multiple tube inlets inthe radiant 320 or cross-over sections 330. When introduced intomultiple coil or tube inlets simultaneously, or nearly simultaneously,the amount of r-pyoil introduced into each coil or tube may not beregulated. In an embodiment or in combination with any of theembodiments mentioned herein, the r-pyoil and/or cracker stream may beintroduced into a common header, which then channels the r-pyoil intomultiple coil or tube inlets.

A single furnace can have at least 1, or at least 2, or at least 3, orat least 4, or at least 5, or at least 6, or at least 7, or at least 8or more, in each case coils. Each coil can be from 5 to 100, 10 to 75,or 20 to 50 meters in length and can include at least 1, or at least 2,or at least 3, or at least 4, or at least 5, or at least 6, or at least7, or at least 8, or at least 10, or at least 12, or at least 14 or moretubes. Tubes of a single coil may be arranged in many configurations andin an embodiment or in combination with any of the embodiments mentionedherein may be connected by one or more 180° (“U”) bends. One example ofa furnace coil 410 having multiple tubes 420 is shown in FIG. 6.

An olefin plant can have a single cracking furnace, or it can have atleast 2, or at least 3, or at least 4, or at least 5, or at least 6, orat least 7, or at least 8 or more cracking furnaces operated inparallel. Any one or each furnace(s) may be gas cracker, or a liquidcracker, or a split furnace. In an embodiment or in combination with anyembodiment mentioned herein or in combination with any of the mentionedembodiments, the furnace is a gas cracker receiving a cracker feedstream containing at least 50 wt. %, or at least 75 wt. %, or at least85 wt. % or at least 90 wt. % ethane, propane, LPG, or a combinationthereof through the furnace, or through at least one coil in a furnace,or through at least one tube in the furnace, based on the weight of allcracker feed to the furnace. In an embodiment or in combination with anyembodiment mentioned herein or in combination with any of the mentionedembodiments, the furnace is a liquid or naphtha cracker receiving acracker feed stream containing at least 50 wt. %, or at least 75 wt. %,or at least 85 wt. % liquid (when measured at 25° C. and 1 atm)hydrocarbons having a carbon number from C₅-C₂₂. through the furnace, orthrough at least one coil in a furnace, or through at least one tube inthe furnace, based on the weight of all cracker feed to the furnace. Inan embodiment or in combination with any embodiment mentioned herein orin combination with any of the mentioned embodiments, the cracker is asplit furnace receiving a cracker feed stream containing at least 50 wt.%, or at least 75 wt. %, or at least 85 wt. % or at least 90 wt. %ethane, propane, LPG, or a combination thereof through the furnace, orthrough at least one coil in a furnace, or through at least one tube inthe furnace, and receiving a cracker feed stream containing at least 0.5wt. %, or at least 0.1 wt. %, or at least 1 wt. %, or at least 2 wt. %,or at least 5 wt. %, or at least 7 wt. %, or at least 10 wt. %, or atleast 13 wt. %, or at least 15 wt. %, or at least 20 wt. % liquid and/orr-pyoil (when measured at 25° C. and 1 atm), each based on the weight ofall cracker feed to the furnace.

Turning now to FIG. 7, several possible locations for introducing ther-pyoil containing feed stream and the non-recycle cracker feed streaminto a cracking furnace are shown.

In an embodiment or in combination with any of the embodiments mentionedherein, an r-pyoil containing feed stream 550 may be combined with thenon-recycle cracker feed 552 upstream of the convection section to forma combined cracker feed stream 554, which may then be introduced intothe convection section 510 of the furnace. Alternatively, or inaddition, the r-pyoil containing feed 550 may be introduced into a firstfurnace coil, while the non-recycle cracker feed 552 is introduced intoa separate or second furnace coil, within the same furnace, or withinthe same convection zone. Both streams may then travel in parallel withone another through the convection section 510 within a convection box512, cross-over 530, and radiant section 520 within a radiant box 522,such that each stream is substantially fluidly isolated from the otherover most, or all, of the travel path from the inlet to the outlet ofthe furnace. The pyoil stream introduced into any heating zone withinthe convection section 510 can flow through the convection section 510and flow through as a vaporized stream 514 b into the radiant box 522.In other embodiments, the r-pyoil containing feed stream 550 may beintroduced into the non-recycle cracker stream 552 as it passes througha furnace coil in the convection section 510 flowing into the cross-oversection 530 of the furnace to form a combined cracker stream 514 a, asalso shown in FIG. 7.

In an embodiment or in combination with any embodiment mentioned hereinor in combination with any of the mentioned embodiments, the r-pyoil 550may be introduced into the first furnace coil, or an additional amountintroduced into the second furnace coil, at either a first heating zoneor a second heating zone as shown in FIG. 7. The r-pyoil 550 may beintroduced into the furnace coil at these locations through a nozzle. Aconvenient method for introducing the feed of r-pyoil is through one ormore dilution steam feed nozzles that are used to feed steam into thecoil in the convection zone. The service of one or more dilution steamnozzles may be employed to inject r-pyoil, or a new nozzle can befastened to the coil dedicated to the injection of the r-pyoil. In anembodiment or in combination with any embodiment mentioned herein or incombination with any of the mentioned embodiments, both steam andr-pyoil can be co-fed through a nozzle into the furnace coil downstreamof the inlet to the coil and upstream of a crossover, optionally at thefirst or second heating zone within the convection zone as shown in FIG.7.

The non-recycle cracker feed stream may be mostly liquid and have avapor fraction of less than 0.25 by volume, or less than 0.25 by weight,or it may be mostly vapor and have a vapor fraction of at least 0.75 byvolume, or at least 0.75 by weight, when introduced into the furnaceand/or when combined with the r-pyoil containing feed. Similarly, ther-pyoil containing feed may be mostly vapor or mostly liquid whenintroduced into the furnace and/or when combined with the non-recyclecracker stream.

In an embodiment or in combination with any of the embodiments mentionedherein, at least a portion or all of the r-pyoil stream or cracker feedstream may be preheated prior to being introduced into the furnace. Asshown in FIG. 8, the preheating can be performed with an indirect heatexchanger 618 heated by a heat transfer media (such as steam, hotcondensate, or a portion of the olefin-containing effluent) or via adirect fired heat exchanger 618. The preheating step can vaporize all ora portion of the stream comprising r-pyoil and may, for example,vaporize at least 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 99 weightpercent of the stream comprising r-pyoil.

The preheating, when performed, can increase the temperature of ther-pyoil containing stream to a temperature that is within about 50, 45,40, 35, 30, 25, 20, 15, 10, 5, or 2° C. of the bubble point temperatureof the r-pyoil containing stream. Additionally, or in the alternative,the preheating can increase the temperature of the stream comprisingr-pyoil to a temperature at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50,55, 60, 65, 70, 75, 80, 85, 90, or 100° C. below the coking temperatureof the stream. In an embodiment or in combination with any of theembodiments mentioned herein, the preheated r-pyoil stream can have atemperature of at least 200, 225, 240, 250, or 260° C. and/or not morethan 375, 350, 340, 330, 325, 320, or 315° C., or at least 275, 300,325, 350, 375, or 400° C. and/or not more than 600, 575, 550, 525, 500,or 475° C. When the atomized liquid (as explained below) is injectedinto the vapor phase, heated cracker stream, the liquid may rapidlyevaporate such that, for example, the entire combined cracker stream isvapor (e.g., 100 percent vapor) within 5, 4, 3, 2, or 1 second afterinjection.

In an embodiment or in combination with any of the embodiments mentionedherein, the heated r-pyoil stream (or cracker stream comprising ther-pyoil and the non-recycle cracker stream) can optionally be passedthrough a vapor-liquid separator to remove any residual heavy or liquidcomponents, when present. The resulting light fraction may then beintroduced into the cracking furnace, alone or in combination with oneor more other cracker streams as described in various embodimentsherein. For example, in an embodiment or in combination with any of theembodiments mentioned herein, the r-pyoil stream can comprise at least1, 2, 5, 8, 10, or 12 weight percent C₁₅ and heavier components. Theseparation can remove at least 50, 55, 60, 65, 70, 75, 80, 85, 90, 95,or 99 weight percent of the heavier components from the r-pyoil stream.

Turning back to FIG. 7, the cracker feed stream (either alone or whencombined with the r-pyoil feed stream) may be introduced into a furnacecoil at or near the inlet of the convection section. The cracker streammay then pass through at least a portion of the furnace coil in theconvection section 510, and dilution steam may be added at some point inorder to control the temperature and cracking severity in the furnace.In an embodiment or in combination with any of the embodiments mentionedherein, the steam may be added upstream of or at the inlet to theconvection section, or it may be added downstream of the inlet to theconvection section—either in the convection section, at the cross-oversection, or upstream of or at the inlet to the radiant section.Similarly, the stream comprising the r-pyoil and the non-recycle crackerstream (alone or combined with the steam) may also be introduced into orupstream or at the inlet to the convection section, or downstream of theinlet to the convection section—either within the convection section, atthe cross-over, or at the inlet to the radiant section. The steam may becombined with the r-pyoil stream and/or cracker stream and the combinestream may be introduced at one or more of these locations, or the steamand r-pyoil and/or non-recycle cracker stream may be added separately.

When combined with steam and fed into or near the cross-over section ofthe furnace, the r-pyoil and/or cracker stream can have a temperature of500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620, 630,640, 650, 660, 670, or 680° C. and/or not more than 850, 840, 830, 820,810, 800, 790, 780, 770, 760, 750, 740, 730, 720, 710, 705, 700, 695,690, 685, 680, 675, 670, 665, 660, 655, or 650° C. The resulting steamand r-pyoil stream can have a vapor fraction of at least 0.75, 0.80,0.85, 0.90, or at least 0.95 by weight, or at least 0.75, 0.80, 0.85,0.90, and 0.95 by volume.

When combined with steam and fed into or near the inlet to theconvection section 510, the r-pyoil and/or cracker stream can have atemperature of at least 30, 35, 40, 45, 50, 55, 60, or 65 and/or notmore than 100, 90, 80, 70, 60, 50, or 45° C.

The amount of steam added may depend on the operating conditions,including feed type and desired product, but can be added to achieve asteam-to-hydrocarbon ratio can be at least 0.10:1, 0.15:1, 0.20:1,0.25:1, 0.27:1, 0.30:1, 0.32:1, 0.35:1, 0.37:1, 0.40:1, 0.42:1, 0.45:1,0.47:1, 0.50:1, 0.52:1, 0.55:1, 0.57:1, 0.60:1, 0.62:1, 0.65:1 and/ornot more than about 1:1. 0.95:1, 0.90:1, 0.85:1, 0.80:1, 0.75:1, 0.72:1,0.70:1, 0.67:1, 0.65:1, 0.62:1, 0.60:1, 0.57:1, 0.55:1, 0.52:1, 0.50:1,or it can be in the range of from 0.1:1 to 1.0:1, 0.15:1 to 0.9:1, 0.2:1to 0.8:1, 0.3:1 to 0.75:1, or 0.4:1 to 0.6:1. When determining the“steam-to-hydrocarbon” ratio, all hydrocarbon components are includedand the ratio is by weight. In an embodiment or in combination with anyof the embodiments mentioned herein, the steam may be produced usingseparate boiler feed water/steam tubes heated in the convection sectionof the same furnace (not shown in FIG. 7). Steam may be added to thecracker feed (or any intermediate cracker stream within the furnace)when the cracker stream has a vapor fraction of 0.60 to 0.95, or 0.65 to0.90, or 0.70 to 0.90.

When the r-pyoil containing feed stream is introduced into the crackingfurnace separately from a non-recycle feed stream, the molar flow rateof the r-pyoil and/or the r-pyoil containing stream may be differentthan the molar flow rate of the non-recycle feed stream. In oneembodiment or in combination with any other mentioned embodiment, thereis provided a method for making one or more olefins by:

(a) feeding a first cracker stream having r-pyoil to a first tube inletin a cracker furnace;

(b) feeding a second cracker stream containing, or predominatelycontaining C₂ to C₄ hydrocarbons to a second tube inlet in the crackerfurnace, wherein said second tube is separate from said first tube andthe total molar flow rate of the first cracker stream fed at the firsttube inlet is lower than the total molar flow rate of the second crackerstream to the second tube inlet, calculated without the effect of steam.The feeding of step (a) and step (b) can be to respective coil inlets.

For example, the molar flow rate of the r-pyoil or the first crackerstream as it passes through a tube in the cracking furnace may be atleast 5, 7, 10, 12, 15, 17, 20, 22, 25, 27, 30, 35, 40, 45, 50, 55, or60 percent lower than the flow rate of the hydrocarbon components (e.g.,C₂-C₄ or C₅-C₂₂) components in the non-recycle feed stream, or thesecond cracker stream, passing through another or second tube. Whensteam is present in both the r-pyoil containing stream, or first crackerstream, and in the second cracker stream or the non-recycle feed stream,the total molar flow rate of the r-pyoil containing stream, or firstcracker stream, (including r-pyoil and dilution steam) may be at least5, 7, 10, 12, 15, 17, 20, 22, 25, 27, 30, 35, 40, 45, 50, 55, or 60percent higher than the total molar flow rate (including hydrocarbon anddilution steam) of the non-recycle cracker feedstock, or second crackerstream (wherein the percentage is calculated as the difference betweenthe two molar flow rates divided by the flow rate of the non-recyclestream).

In an embodiment or in combination with any of the embodiments mentionedherein, the molar flow rate of the r-pyoil in the r-pyoil containingfeed stream (first cracker stream) within the furnace tube may be atleast 0.01, 0.02, 0.025, 0.03, 0.035 and/or not more than 0.06, 0.055,0.05, 0.045 kmol-lb/hr lower than the molar flow rate of the hydrocarbon(e.g., C₂-C₄ or C₅-C₂₂) in the non-recycle cracker stream (secondcracker stream). In an embodiment or in combination with any of theembodiments mentioned herein, the molar flow rates of the r-pyoil andthe cracker feed stream may be substantially similar, such that the twomolar flow rates are within 0.005, 0.001, or 0.0005 kmol-lb/hr of oneanother. The molar flow rate of the r-pyoil in the furnace tube can beat least 0.0005, 0.001, 0.0025, 0.005, 0.01, 0.02, 0.03, 0.04, 0.05,0.06, 0.07, 0.08, 0.09, 0.10, 0.11, 0.12, 0.13, 0.14, or 0.15 kilomoles-pound per hour (kmol-lb/hr) and/or not more than 0.25, 0.24, 0.23,0.22, 0.21, 0.20, 0.19, 0.18, 0.17, 0.16, 0.15, 0.14, 0.13, 0.08, 0.05,0.025, 0.01, or 0.008 kmol-lb/hr, while the molar flow rate of thehydrocarbon components in the other coil or coils can be at least 0.02,0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.11, 0.12, 0.13, 0.14,0.15, 0.16, 0.17, 0.18 and/or not more than 0.30, 0.29, 0.28, 0.27,0.26, 0.25, 0.24, 0.23, 0.22, 0.21, 0.20, 0.19, 0.18, 0.17, 0.16, 0.15kmol-lb/hr.

In an embodiment or in combination with any of the embodiments mentionedherein, the total molar flow rate of the r-pyoil containing stream(first cracker stream) can be at least 0.01, 0.02, 0.03, 0.04, 0.05,0.06, 0.07, 0.08, 0.09 and/or not more than 0.30, 0.25, 0.20, 0.15,0.13, 0.10, 0.09, 0.08, 0.07, or 0.06 kmol-lb/hr lower than the totalmolar flow rate of the non-recycle feed stream (second cracker stream),or the same as the total molar flow rate of the non-recycle feed stream(second cracker stream). The total molar flow rate of the r-pyoilcontaining stream (first cracker stream) can be at least 0.01, 0.02,0.03, 0.04, 0.05, 0.06, 0.07 and/or not more than 0.10, 0.09, 0.08,0.07, or 0.06 kmol-lb/hr higher than the total molar flow rate of thesecond cracker stream, while the total molar flow rate of thenon-recycle feed stream (second cracker stream) can be at least 0.20,0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, 0.31, 0.32,0.33 and/or not more than 0.50, 0.49, 0.48, 0.47. 0.46, 0.45, 0.44,0.43, 0.42, 0.41, 0.40 kmol-lb/hr.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil containing stream, or first cracker stream, has asteam-to-hydrocarbon ratio that is at least 5, 10, 15, 20, 25, 30, 35,40, 45, 50, 55, 60, 65, 70, 75, or 80 percent different than thesteam-to-hydrocarbon ratio of the non-recycle feed stream, or secondcracker stream. The steam-to-hydrocarbon ratio can be higher or lower.For example, the steam-to-hydrocarbon ratio of the r-pyoil containingstream or first cracker stream can be at least 0.01, 0.025, 0.05, 0.075,0.10, 0.125, 0.15, 0.175, or 0.20 and/or not more than 0.3, 0.27, 0.25,0.22, or 0.20 different than the steam-to-hydrocarbon ratio of thenon-recycle feed stream or second cracker stream. Thesteam-to-hydrocarbon ratio of the r-pyoil containing stream or firstcracker stream can be at least 0.3, 0.32, 0.35, 0.37, 0.4, 0.42, 0.45,0.47, 0.5 and/or not more than 0.7, 0.67, 0.65, 0.62, 0.6, 0.57, 0.55,0.52, or 0.5, and the steam-to-hydrocarbon ratio of the non-recyclecracker feed or second cracker stream can be at least 0.02, 0.05, 0.07,0.10, 0.12, 0.15, 0.17, 0.20, 0.25 and/or not more than 0.45, 0.42,0.40, 0.37, 0.35, 0.32, or 0.30.

In an embodiment or in combination with any embodiments mentionedherein, the temperature of the r-pyoil containing stream as it passesthrough a cross-over section in the cracking furnace can be differentthan the temperature of the non-recycle cracker feed as it passesthrough the cross-over section, when the streams are introduced into andpassed through the furnace separately. For example, the temperature ofthe r-pyoil stream (or first cracker stream) as it passes through thecross-over section may be at least 0.01, 0.5, 1, 1.5, 2, 5, 10, 15, 20,25, 30, 35, 40, 45, 50, 55, 60, 65, 70, or 75 percent different than thetemperature of the non-recycle hydrocarbon stream, or second crackerstream (e.g., C₂-C₄ or C₅-C₂₂) passing through the cross-over section inanother coil. The percentage can be calculated based on the temperatureof the non-recycle stream according to the following formula:

[(temperature of r-pyoil stream−temperature of non-recycle crackerstream)]/(temperature of non-recycle cracker steam),expressed as apercentage.

The difference can be higher or lower. The average temperature of ther-pyoil containing stream at the cross-over section can be at least 400,425, 450, 475, 500, 525, 550, 575, 580, 585, 590, 595, 600, 605, 610,615, 620, or 625° C. and/or not more than 705, 700, 695, 690, 685, 680,675, 670, 665, 660, 655, 650, 625, 600, 575, 550, 525, or 500° C., whilethe average temperature of the non-recycle cracker feed can be at least401, 426, 451, 476, 501, 526, 551, 560, 565, 570, 575, 580, 585, 590,595, 600, 605, 610, 615, 620, or 625° C. and/or not more than 705, 700,695, 690, 685, 680, 675, 670, 665, 660, 655, 650, 625, 600, 575, 550,525, or 500° C.

The heated cracker stream, which usually has a temperature of at least500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620, 630,640, 650, 660, 670, or 680° C. and/or not more than 850, 840, 830, 820,810, 800, 790, 780, 770, 760, 750, 740, 730, 720, 710, 705, 700, 695,690, 685, 680, 675, 670, 665, 660, 655, or 650° C., or in the range offrom 500 to 710° C., 620 to 740° C., 560 to 670° C., or 510 to 650° C.,may then pass from the convection section of the furnace to the radiantsection via the cross-over section.

In an embodiment or in combination with any of the embodiments mentionedherein, the r-pyoil containing feed stream may be added to the crackerstream at the cross-over section. When introduced into the furnace inthe cross-over section, the r-pyoil may be at least partially vaporizedby, for example, preheating the stream in a direct or indirect heatexchanger. When vaporized or partially vaporized, the r-pyoil containingstream has a vapor fraction of at least 0.5, 0.55, 0.6, 0.65, 0.7, 0.75,0.8, 0.85, 0.9, 0.95, or 0.99 by weight, or in one embodiment or incombination with any mentioned embodiments, by volume.

When the r-pyoil containing stream is atomized prior to entering thecross-over section, the atomization can be performed using one or moreatomizing nozzles. The atomization can take place within or outside thefurnace. In an embodiment or in combination with any of the embodimentsmentioned herein, an atomizing agent may be added to the r-pyoilcontaining stream during or prior to its atomization. The atomizingagent can include steam, or it may include predominantly ethane,propane, or combinations thereof. When used the atomizing agent may bepresent in the stream being atomized (e.g., the r-pyoil containingcomposition) in an amount of at least 1, 2, 4, 5, 8, 10, 12, 15, 10, 25,or 30 weight percent and/or not more than 50, 45, 40, 35, 30, 25, 20,15, or 10 weight percent.

The atomized or vaporized stream of r-pyoil may then be injected into orcombined with the cracker stream passing through the cross-over section.At least a portion of the injecting can be performed using at least onespray nozzle. At least one of the spray nozzles can be used to injectthe r-pyoil containing stream into the cracker feed stream may beoriented to discharge the atomized stream at an angle within about 45,50, 35, 30, 25, 20, 15, 10, 5, or 0° from the vertical. The spray nozzleor nozzles may also be oriented to discharge the atomized stream into acoil within the furnace at an angle within about 30, 25, 20, 15, 10, 8,5, 2, or 1° of being parallel, or parallel, with the axial centerline ofthe coil at the point of introduction. The step of injecting theatomized r-pyoil may be performed using at least two, three, four, five,six or more spray nozzles, in the cross-over and/or convection sectionof the furnace.

In an embodiment or in combination with any embodiments mentionedherein, atomized r-pyoil can be fed, alone or in combination with an atleast partially non-recycle cracker stream, into the inlet of one ormore coils in the convection section of the furnace. The temperature ofsuch an atomization can be at least 30, 35, 40, 45, 50, 55, 60, 65, 70,75, or 80° C. and/or not more than 120, 110, 100, 90, 95, 80, 85, 70,65, 60, or 55° C.

In an embodiment or in combination with any embodiments mentionedherein, the temperature of the atomized or vaporized stream can be atleast 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 75, 100, 125, 150, 175,200, 225, 250, 275, 300, 325, 350° C. and/or not more than 550, 525,500, 475, 450, 425, 400, 375, 350, 325, 300, 275, 250, 225, 200, 175,150, 125, 100, 90, 80, 75, 70, 60, 55, 50, 45, 40, 30, or 25° C. coolerthan the temperature of the cracker stream to which it is added. Theresulting combined cracker stream comprises a continuous vapor phasewith a discontinuous liquid phase (or droplets or particles) dispersedtherethrough. The atomized liquid phase may comprise r-pyoil, while thevapor phase may include predominantly C₂-C₄ components, ethane, propane,or combinations thereof. The combined cracker stream may have a vaporfraction of at least 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, or 0.99 by weight,or in one embodiment or in combination with any mentioned embodiments,by volume.

The temperature of the cracker stream passing through the cross-oversection can be at least 500, 510, 520, 530, 540, 550, 555, 560, 565,570, 575, 580, 585, 590, 595, 600, 605, 610, 615, 620, 625, 630, 635,640, 645, 650, 660, 670, or 680° C. and/or not more than 850, 840, 830,820, 810, 800, 795, 790, 785, 780, 775, 770, 765, 760, 755, 750, 745,740, 735, 730, 725, 720, 715, 710, 705, 700, 695, 690, 685, 680, 675,670, 665, 660, 655, 650, 645, 640, 635, or 630° C., or in the range offrom 620 to 740° C., 550 to 680° C., 510 to 630° C.

The resulting cracker feed stream then passes into the radiant section.In an embodiment or in combination with any of the embodiments mentionedherein, the cracker stream (with or without the r-pyoil) from theconvection section may be passed through a vapor-liquid separator toseparate the stream into a heavy fraction and a light fraction beforecracking the light fraction further in the radiant section of thefurnace. One example of this is illustrated in FIG. 8.

In an embodiment or in combination with any of the embodiments mentionedherein, the vapor-liquid separator 640 may comprise a flash drum, whilein other embodiments it may comprise a fractionator. As the stream 614passes through the vapor-liquid separator 640, a gas stream impinges ona tray and flows through the tray, as the liquid from the tray fall toan underflow 642. The vapor-liquid separator may further comprise ademister or chevron or other device located near the vapor outlet forpreventing liquid carry-over into the gas outlet from the vapor-liquidseparator 640.

Within the convection section 610, the temperature of the cracker streammay increase by at least 50, 75, 100, 150, 175, 200, 225, 250, 275, or300° C. and/or not more than about 650, 600, 575, 550, 525, 500, 475,450, 425, 400, 375, 350, 325, 300, or 275° C., so that the passing ofthe heated cracker stream exiting the convection section 610 through thevapor-liquid separator 640 may be performed at a temperature of least400, 425, 450, 475, 500, 525, 550, 575, 600, 625, 650° C. and/or notmore than 800, 775, 750, 725, 700, 675, 650, 625° C. When heaviercomponents are present, at least a portion or nearly all of the heavycomponents may be removed in the heavy fraction as an underflow 642. Atleast a portion of the light fraction 644 from the separator 640 may beintroduced into the cross-over section or the radiant zone tubes 624after the separation, alone or in combination with one or more othercracker streams, such as, for example, a predominantly C₅-C₂₂hydrocarbon stream or a C₂-C₄ hydrocarbon stream.

Referencing FIGS. 5 and 6, the cracker feed stream (either thenon-recycle cracker feed stream or when combined with the r-pyoil feedstream) 350 and 650 may be introduced into a furnace coil at or near theinlet of the convection section. The cracker feed stream may then passthrough at least a portion of the furnace coil in the convection section310 and 610, and dilution steam 360 and 660 may be added at some pointin order to control the temperature and cracking severity in the radiantsection 320 and 620. The amount of steam added may depend on the furnaceoperating conditions, including feed type and desired productdistribution, but can be added to achieve a steam-to-hydrocarbon ratioin the range of from 0.1 to 1.0, 0.15 to 0.9, 0.2 to 0.8, 0.3 to 0.75,or 0.4 to 0.6, calculated by weight. In an embodiment or in combinationwith any of the embodiments mentioned herein, the steam may be producedusing separate boiler feed water/steam tubes heated in the convectionsection of the same furnace (not shown in FIG. 5). Steam 360 and 660 maybe added to the cracker feed (or any intermediate cracker feed streamwithin the furnace) when the cracker feed stream has a vapor fraction of0.60 to 0.95, or 0.65 to 0.90, or 0.70 to 0.90 by weight, or in oneembodiment or in combination with any mentioned embodiments, by volume.

The heated cracker stream, which usually has a temperature of at least500, or at least 510, or at least 520, or at least 530, or at least 540,or at least 550, or at least 560, or at least 570, or at least 580, orat least 590, or at least 600, or at least 610, or at least 620, or atleast 630, or at least 640, or at least 650, or at least 660, or atleast 670, or at least 680, in each case ° C. and/or not more than 850,or not more than 840, or not more than 830, or not more than 820, or notmore than 810, or not more than 800, or not more than 790, or not morethan 780, or not more than 770, or not more than 760, or not more than750, or not more than 740, or not more than 730, or not more than 720,or not more than 710, or not more than 705, or not more than 700, or notmore than 695, or not more than 690, or not more than 685, or not morethan 680, or not more than 675, or not more than 670, or not more than665, or not more than 660, or not more than 655, or not more than 650,in each case ° C., or in the range of from 500 to 710° C., 620 to 740°C., 560 to 670° C., or 510 to 650° C., may then pass from the convectionsection 610 of the furnace to the radiant section 620 via the cross-oversection 630. In an embodiment or in combination with any of theembodiments mentioned herein, the r-pyoil containing feed stream 550 maybe added to the cracker stream at the cross-over section 530 as shown inFIG. 6. When introduced into the furnace in the cross-over section, ther-pyoil may be at least partially vaporized or atomized prior to beingcombined with the cracker stream at the cross-over. The temperature ofthe cracker stream passing through the cross-over 530 or 630 can be atleast 400, 425, 450, 475, or at least 500, or at least 510, or at least520, or at least 530, or at least 540, or at least 550, or at least 560,or at least 570, or at least 580, or at least 590, or at least 600, orat least 610, or at least 620, or at least 630, or at least 640, or atleast 650, or at least 660, or at least 670, or at least 680, in eachcase ° C. and/or not more than 850, or not more than 840, or not morethan 830, or not more than 820, or not more than 810, or not more than800, or not more than 790, or not more than 780, or not more than 770,or not more than 760, or not more than 750, or not more than 740, or notmore than 730, or not more than 720, or not more than 710, or not morethan 705, or not more than 700, or not more than 695, or not more than690, or not more than 685, or not more than 680, or not more than 675,or not more than 670, or not more than 665, or not more than 660, or notmore than 655, or not more than 650, in each case ° C., or in the rangeof from 620 to 740° C., 550 to 680° C., 510 to 630° C.

The resulting cracker feed stream then passes through the radiantsection, wherein the r-pyoil containing feed stream is thermally crackedto form lighter hydrocarbons, including olefins such as ethylene,propylene, and/or butadiene. The residence time of the cracker feedstream in the radiant section can be at least 0.1, or at least 0.15, orat least 0.2, or at least 0.25, or at least 0.3, or at least 0.35, or atleast 0.4, or at least 0.45, in each case seconds and/or not more than2, or not more than 1.75, or not more than 1.5, or not more than 1.25,or not more than 1, or not more than 0.9, or not more than 0.8, or notmore than 0.75, or not more than 0.7, or not more than 0.65, or not morethan 0.6, or not more than 0.5, in each case seconds. The temperature atthe inlet of the furnace coil is at least 500, or at least 510, or atleast 520, or at least 530, or at least 540, or at least 550, or atleast 560, or at least 570, or at least 580, or at least 590, or atleast 600, or at least 610, or at least 620, or at least 630, or atleast 640, or at least 650, or at least 660, or at least 670, or atleast 680, in each case ° C. and/or not more than 850, or not more than840, or not more than 830, or not more than 820, or not more than 810,or not more than 800, or not more than 790, or not more than 780, or notmore than 770, or not more than 760, or not more than 750, or not morethan 740, or not more than 730, or not more than 720, or not more than710, or not more than 705, or not more than 700, or not more than 695,or not more than 690, or not more than 685, or not more than 680, or notmore than 675, or not more than 670, or not more than 665, or not morethan 660, or not more than 655, or not more than 650, in each case ° C.,or in the range of from 550 to 710° C., 560 to 680° C., or 590 to 650°C., or 580 to 750° C., 620 to 720° C., or 650 to 710° C.

The coil outlet temperature can be at least 640, or at least 650, or atleast 660, or at least 670, or at least 680, or at least 690, or atleast 700, or at least 720, or at least 730, or at least 740, or atleast 750, or at least 760, or at least 770, or at least 780, or atleast 790, or at least 800, or at least 810, or at least 820, in eachcase ° C. and/or not more than 1000, or not more than 990, or not morethan 980, or not more than 970, or not more than 960, or not more than950, or not more than 940, or not more than 930, or not more than 920,or not more than 910, or not more than 900, or not more than 890, or notmore than 880, or not more than 875, or not more than 870, or not morethan 860, or not more than 850, or not more than 840, or not more than830, in each case ° C., in the range of from 730 to 900° C., 750 to 875°C., or 750 to 850° C.

The cracking performed in the coils of the furnace may include crackingthe cracker feed stream under a set of processing conditions thatinclude a target value for at least one operating parameter. Examples ofsuitable operating parameters include, but are not limited to maximumcracking temperature, average cracking temperature, average tube outlettemperature, maximum tube outlet temperature, and average residencetime. When the cracker stream further includes steam, the operatingparameters may include hydrocarbon molar flow rate and total molar flowrate. When two or more cracker streams pass through separate coils inthe furnace, one of the coils may be operated under a first set ofprocessing conditions and at least one of the other coils may beoperated under a second set or processing conditions. At least onetarget value for an operating parameter from the first set of processingconditions may differ from a target value for the same parameter in thesecond set of conditions by at least 0.01, 0.03, 0.05, 0.1, 0.25, 0.5,1, 2, 5, 7, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80,85, 90, or 95 percent and/or not more than about 95, 90, 85, 80, 75, 70,65, 60, 55, 50, 45, 40, 35, 30, 25, 20, or 15 percent. Examples include0.01 to 30, 0.01 to 20, 0.01 to 15, 0.03 to 15 percent. The percentageis calculated according to the following formula:

[(measured value for operating parameter)−(target value for operatingparameter]/[(target value for operating parameter)], expressed as apercentage. As used herein, the term “different,” means higher or lower.

The coil outlet temperature can be at least 640, 650, 660, 670, 680,690, 700, 720, 730, 740, 750, 760, 770, 780, 790, 800, 810, 820° C.and/or not more than 1000, 990, 980, 970, 960, 950, 940, 930, 920, 910,900, 890, 880, 875, 870, 860, 850, 840, 830° C., in the range of from730 to 900° C., 760 to 875° C., or 780 to 850° C.

In an embodiment or in combination with any of the embodiments mentionedherein, the addition of r-pyoil to a cracker feed stream may result inchanges to one or more of the above operating parameters, as compared tothe value of the operating parameter when an identical cracker feedstream is processed in the absence of r-pyoil. For example, the valuesof one or more of the above parameters may be at least 0.01, 0.03, 0.05,0.1, 0.25, 0.5, 1, 2, 5, 7, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60,65, 70, 75, 80, 85, 90, or 95 percent different (e.g., higher or lower)than the value for the same parameter when processing an identical feedstream without r-pyoil, ceteris paribus. The percentage is calculatedaccording to the following formula:

[(measured value for operating parameter)−(target value for operatingparameter]/[(target value for operating parameter)], expressed as apercentage.

One example of an operating parameter that may be adjusted with theaddition of r-pyoil to a cracker stream is coil outlet temperature. Forexample, in an embodiment or in combination with any embodimentmentioned herein, the cracking furnace may be operated to achieve afirst coil outlet temperature (COT1) when a cracker stream having nor-pyoil is present. Next, r-pyoil may be added to the cracker stream,via any of the methods mentioned herein, and the combined stream may becracked to achieve a second coil outlet temperature (COT2) that isdifferent than COT1.

In some cases, when the r-pyoil is heavier than the cracker stream, COT2may be less than COT1, while, in other case, when the r-pyoil is lighterthan the cracker stream, COT2 may be greater than or equal to COT1. Whenthe r-pyoil is lighter than the cracker stream, it may have a 50%boiling point that is at least 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50and/or not more than 80, 75, 70, 65, 60, 55, or 50 percent higher thanthe 50% boiling point of the cracker stream. The percentage iscalculated according to the following formula:

[(50% boiling point of r-pyoil in ° R)−(50% boiling point of crackerstream)]/[(50% boiling point of cracker stream)], expressed as apercentage.

Alternatively, or in addition, the 50% boiling point of the r-pyoil maybe at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75,80, 85, 90, 95, or 100° C. and/or not more than 300, 275, 250, 225, or200° C. lower than the 50% boiling point of the cracker stream. Heaviercracker streams can include, for example, vacuum gas oil (VGO),atmospheric gas oil (AGO), or even coker gas oil (CGO), or combinationsthereof.

When the r-pyoil is lighter than the cracker stream, it may have a 50%boiling point that is at least 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50and/or not more than 80, 75, 70, 65, 60, 55, or 50 percent lower thanthe 50% boiling point of the cracker stream. The percentage iscalculated according to the following formula:

[(50% boiling point of r-pyoil)−(50% boiling point of crackerstream)]/[(50% boiling point of cracker stream)], expressed as apercentage.

Additionally, or in the alternative, the 50% boiling point of ther-pyoil may be at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60,65, 70, 75, 80, 85, 90, 95, or 100° C. and/or not more than 300, 275,250, 225, or 200° C. higher than the 50% boiling point of the crackerstream. Lighter cracker streams can include, for example, LPG, naphtha,kerosene, natural gasoline, straight run gasoline, and combinationsthereof.

In some cases, COT1 can be at least 5, 10, 15, 20, 25, 30, 35, 40, 45,50° C. and/or not more than about not more than 150, 140, 130, 125, 120,110, 105, 100, 90, 80, 75, 70, or 65° C. different (higher or lower)than COT2, or COT1 can be at least 0.3, 0.6, 1, 2, 5, 10, 15, 20, or 25and/or not more than 80, 75, 70, 65, 60, 50, 45, or 40 percent differentthan COT2 (with the percentage here defined as the difference betweenCOT1 and COT2 divided by COT1, expressed as a percentage). At least oneor both of COT1 and COT2 can be at least 730, 750, 77, 800, 825, 840,850, 860, 870, 880, 890, 900, 910, 920, 930, 940, 950, 960, 970, 980,990 and/or not more than 1200, 1175, 1150, 1140, 1130, 1120, 1110, 1100,1090, 1080, 1070, 1060, 1050, 1040, 1030, 1020, 1010, 1000, 990, 980,970, 960 950, 940, 930, 920, 910, or 900° C.

In an embodiment or in combination with any of the embodiments mentionedherein, the mass velocity of the cracker feed stream through at leastone, or at least two radiant coils (for clarity as determine across theentire coil as opposed to a tube within a coil) is in the range of 60 to165 kilograms per second (kg/s) per square meter (m2) of cross-sectionalarea (kg/s/m2), 60 to 130 (kg/s/m2), 60 to 110 (kg/s/m2), 70 to 110(kg/s/m2), or 80 to 100 (kg/s/m2). When steam is present, the massvelocity is based on the total flow of hydrocarbon and steam.

In one embodiment or in combination with any mentioned embodiments,there is provided a method for making one or more olefins by:

-   -   (a) cracking a cracker stream in a cracking unit at a first coil        outlet temperature (COT1);    -   (b) subsequent to step (a), adding a stream comprising a recycle        content pyrolysis oil composition (r-pyoil) to said cracker        stream to form a combined cracker stream; and    -   (c) cracking said combined cracker stream in said cracking unit        at a second coil outlet temperature (COT2), wherein said second        coil outlet temperature is lower, or at least 3° C. lower, or at        least 5° C. lower than said first coil outlet temperature.

The reason or cause for the temperature drop in the second coil outlettemperature (COT2) is not limited, provided that COT2 is lower than thefirst coil outlet temperature (COT1). In one embodiment or incombination with any mentioned embodiments, In one embodiment or incombination with any other mentioned embodiments, the COT2 temperatureon the r-pyoil fed coils can be set to a temperature that lower than, orat least 1, 2, 3, 4, or at least 5° C. lower than COT1 (“Set” Mode), orit can be allowed to change or float without setting the temperature onthe r-pyoil fed coils (“Free Float” Mode”).

The COT2 can be set at least 5° C. lower than COT1 in a Set Mode. Allcoils in a furnace can be r-pyoil containing feed streams, or at least1, or at least two of the coils can be r-pyoil containing feed streams.In either case, at least one of the r-pyoil containing coils can be in aSet Mode. By reducing the cracking severity of the combined crackingstream, one can take advantage of the lower heat energy required tocrack r-pyoil when it has an average number average molecular weightthat is higher than the cracker feed stream, such as a gaseous C₂-C₄feed. While the cracking severity on the cracker feed (e.g. C₂-C₄) canbe reduced and thereby increase the amount of unconverted C₂-C₄ feed ina single pass, the higher amount of unconverted feed (e.g. C₂-C₄ feed)is desirable to increase the ultimate yield of olefins such as ethyleneand/or propylene through multiple passes by recycling the unconvertedC₂-C₄ feed through the furnace. Optionally, other cracker products, suchas the aromatic and diene content, can be reduced.

In one embodiment or in combination with any mentioned embodiments, Inone embodiment or in combination with any other mentioned embodiments,the COT2 in a coil can be fixed in a Set Mode to be lower than, or atleast 1, 2, 3, 4, or at least 5° C. lower than the COT1 when thehydrocarbon mass flow rate of the combined cracker stream in at leastone coil is the same as or less than the hydrocarbon mass flow rate ofthe cracker stream in step (a) in said coil. The hydrocarbon mass flowrate includes all hydrocarbons (cracker feed and if present the r-pyoiland/or natural gasoline or any other types of hydrocarbons) and otherthan steam. Fixing the COT2 is advantageous when the hydrocarbon massflow rate of the combined cracker stream in step (b) is the same as orless than the hydrocarbon mass flow rate of the cracker stream in step(a) and the pyoil has a higher average molecular weight than the averagemolecular weight of the cracker stream. At the same hydrocarbon massflow rates, when pyoil has a heavier average molecular weight than thecracker stream, the COT2 will tend to rise with the addition of pyoilbecause the higher molecular weight molecules require less thermalenergy to crack. If one desires to avoid overcracking the pyoil, thelowered COT2 temperature can assist to reduce by-product formation, andwhile the olefin yield in the singe pass is also reduced, the ultimateyield of olefins can be satisfactory or increased by recyclingunconverted cracker feed through the furnace.

In a Set Mode, the temperature can be fixed or set by adjusting thefurnace fuel rate to burners.

In one embodiment or in combination with any other mentionedembodiments, the COT2 is in a Free Float Mode and is as a result offeeding pyoil and allowing the COT2 to rise or fall without fixing atemperature to the pyoil fed coils. In this embodiment, not all of thecoils contain r-pyoil. The heat energy supplied to the r-pyoilcontaining coils can be supplied by keeping constant temperature on, orfuel feed rate to the burners on the non-recycle cracker feed containingcoils. Without fixing or setting the COT2, the COT2 can be lower thanCOT1 when pyoil is fed to the cracker stream to form a combined crackerstream that has a higher hydrocarbon mass flow rate than the hydrocarbonmass flow rate of the cracker stream in step (a). Pyoil added to acracker feed to increase the hydrocarbon mass flow rate of the combinedcracker feed lowers the COT2 and can outweigh the temperature riseeffect of using a higher average molecular weight pyoil. These effectscan be seen while other cracker conditions are held constant, such asthe dilution steam ratio, feed locations, composition of the crackerfeed and pyoil, and fuel feed rates to the firebox burners in thefurnace on the tubes containing only cracker feed and no feed ofr-pyoil.

The COT2 can be lower than, or at least 1, 2, 3, 4, 5, 8, 10, 12, 15,18, 20, 25, 30, 35, 40, 45, 50° C. and/or not more than about not morethan 150, 140, 130, 125, 120, 110, 105, 100, 90, 80, 75, 70, or 65° C.lower than COT1.

Independent of the reason or cause of the temperature drop in COT2, thetime period for engaging step (a) is flexible, but ideally, step (a)reaches a steady state before engaging step (b). In one embodiment or incombination with any mentioned embodiments, step (a) is in operation forat least 1 week, or at least 2 weeks, or at least 1 month, or at least 3months, or at least 6 months, or at least 1 year, or at least 1.5 years,or at least 2 years. The step (a) can be represented by a crackerfurnace in operation that has never accepted a feed of pyoil or acombined feed of cracker feed and pyoil. Step (b) can be the first timea furnace has accepted a feed of pyoil or a combined cracker feedcontaining pyoil. In one embodiment or in combination with any othermentioned embodiments, steps (a) and (b) can be cycled multiple timesper year, such as at least 2x/yr, or at least 3x/yr, or at least 4x/yr,or at least 5x/yr, or at least 6x/yr, or at least 8x/yr, or at least12x/yr, as measured on a calendar year. Campaigning a feed of pyoil isrepresentative of multiple cycling of steps (a) and (b). When the feedsupply of pyoil is exhausted or shut off, the COT1 is allowed to reach asteady state temperature before engaging step (b).

Alternatively, the feed of pyoil to a cracker feed can be continuousover the entire course of at least 1 calendar year, or at least 2calendar years.

In one embodiment or in combination with any other mentionedembodiments, the cracker feed composition used in steps (a) and (b)remains unchanged, allowing for regular compositional variationsobserved during the course of a calendar year. In one embodiment or incombination with any other mentioned embodiments, the flow of crackerfeed in step (a) is continuous and remains continuous as pyoil is to thecracker feed to make a combined cracker feed. The cracker feed in steps(a) and (b) can be drawn from the same source, such as the sameinventory or pipeline.

In one embodiment or in combination with any mentioned embodiments, theCOT2 is lower than, or at least 1, 2, 3, 4, or at least 5° C. lower forat least 30% of the time that the pyoil is fed to the cracker stream toform the combined cracker stream, or at least 40% of the time, or atleast 50% of the time, or at least 60% of the time, or at least 70% ofthe time, or at least 80% of the time, or at least 85% of the time, orat least 90% of the time, or at least 95% of the time, the time measuredas when all conditions, other than COT's, are held constant, such ascracker and pyoil feed rates, steam ratio, feed locations, compositionof the cracker feed and pyoil, etc.

In one embodiment or in combination with any mentioned embodiments, thehydrocarbon mass flow rate of combined cracker feed can be increased.There is now provided a method for making one or more olefins by:

-   -   (a) cracking a cracker stream in a cracking unit at a first        hydrocarbon mass flow rate (MF1);    -   (b) subsequent to step (a), adding a stream comprising a recycle        content pyrolysis oil composition (r-pyoil) to said cracker        stream to form a combined cracker stream having a second        hydrocarbon mass flow rate (MF2) that is higher than MF1; and    -   (c) cracking said combined cracker stream at MF2 in said        cracking unit to obtain an olefin-containing effluent that has a        combined output of ethylene and propylene that same as or higher        than the output of ethylene and propylene obtained by cracking        only said cracker stream at MF1.

The output refers to the production of the target compounds in weightper unit time, for example, kg/hr. Increasing the mass flow rate of thecracker stream by addition of r-pyoil can increase the output ofcombined ethylene and propylene, thereby increasing the throughput ofthe furnace. Without being bound to a theory, it is believed that thisis made possible because the total energy of reaction is not asendothermic with the addition of pyoil relative to total energy ofreaction with a lighter cracker feed such as propane or ethane. Sincethe heat flux on the furnace is limited and the total heat of reactionof pyoil is less endothermic, more of the limited heat energy becomesavailable to continue cracking the heavy feed per unit time. The MF2 canbe increased by at least 1, 2, 3, 4, 5, 7, 10, 10, 13, 15, 18, or 20%through a r-pyoil fed coil, or can be increased by at least 1, 2, 3, 5,7, 10, 10, 13, 15, 18, or 20% as measured by the furnace output providedthat at least one coil processes r-pyoil. Optionally, the increase incombined output of ethylene and propylene can be accomplished withoutvarying the heat flux in the furnace, or without varying the r-pyoil fedcoil outlet temperature, or without varying the fuel feed rate to theburners assigned to heat the coils containing only non-recycle contentcracker feed, or without varying the fuel feed rate to any of theburners in the furnace. The MF2 higher hydrocarbon mass flow rate in ther-pyoil containing coils can be through one or at least one coil in afurnace, or two or at least two, or 50% or at least 50%, or 75% or atleast 75%, or through all of the coils in a furnace.

The olefin-containing effluent stream can have a total output ofpropylene and ethylene from the combined cracker stream at MF2 that isthe same as or higher than the output of propylene and ethylene of aneffluent stream obtained by cracking the same cracker feed but withoutr-pyoil by at least 0.5%, or at least 1%, or at least 2%, or at least2.5%, determined as:

${\%{increase}} = {\frac{{{Omf}2} - {{Omf}1}}{{Omf}1} \times 100}$

-   -   where O_(mf1) is the combined output of propylene and ethylene        content in the cracker effluent at MF1 made without r-pyoil; and    -   O_(mf2) is the combined output of propylene and ethylene content        in the cracker effluent at MF2 made with r-pyoil.

The olefin-containing effluent stream can have a total output ofpropylene and ethylene from the combined cracker stream at MF2 that isleast 1, 5, 10, 15, 20%, and/or up to 80, 70, 65% of the mass flow rateincrease between MF2 and MF1 on a percentage basis. Examples of suitableranges include 1 to 80, or 1 to 70, or 1 to 65, or 5 to 80, or 5 to 70,or 5 to 65, or 10 to 80, or 10 to 70, or 10 to 65, or 15 to 80, or 15 to70, or 15 to 65, or 20 to 80, or 20 to 70, or 20 to 65, or 25 to 80, or25 to 70, or 26 to 65, or 35 to 80, or 35 to 70, or 35 to 65, or 40 to80, or 40 to 70, or 40 to 65, each expressed as a percent %. Forexample, if the percentage difference between MF2 and MF1 is 5%, and thetotal output of propylene and ethylene is increased by 2.5%, the olefinincrease as a function of mass flow increase is 50% (2.5%/5% x 100).This can be determined as:

${\%{relative}{increase}} = {\frac{\Delta O\%}{\Delta{MF}\%} \times 100}$

-   -   where ΔO % is percentage increase between the combined output of        propylene and ethylene content in the cracker effluent at MF1        made without r-pyoil and    -   MF2 made with r-pyoil (using the aforementioned equation); and    -   ΔMF % is the percentage increase of MF2 over MF1.

Optionally, the olefin-containing effluent stream can have a total wt. %of propylene and ethylene from the combined cracker stream at MF2 thatis the same as or higher than the wt. % of propylene and ethylene of aneffluent stream obtained by cracking the same cracker feed but withoutr-pyoil by at least 0.5%, or at least 1%, or at least 2%, or at least2.5%, determined as:

${\%{increase}} = {\frac{{{Emf}2} - {{Emf}1}}{{Emf}1} \times 100}$

where E_(mf1) is the combined wt. % of propylene and ethylene content inthe cracker effluent at MF1 made without r-pyoil; andE_(mf2) is the combined wt. % of propylene and ethylene content in thecracker effluent at MF2 made with r-pyoil.

There is also provided a method for making one or more olefins, saidmethod comprising:

-   -   (a) cracking a cracker stream in a cracking furnace to provide a        first olefin-containing effluent exiting the cracking furnace at        a first coil outlet temperature (COT1);    -   (b) subsequent to step (a), adding a stream comprising a recycle        content pyrolysis oil composition (r-pyoil) to said cracker        stream to form a combined cracker stream; and    -   (c) cracking said combined cracker stream in said cracking unit        to provide a second olefin-containing effluent exiting the        cracking furnace at a second coil outlet temperature (COT2),

wherein, when said r-pyoil is heavier than said cracker stream, COT2 isequal to or less than COT1,

wherein, when said r-pyoil is lighter than said cracker stream, COT2 isgreater than or equal to COT1.

In this method, the embodiments described above for a COT2 at lower thanCOT1 are also applicable here. The COT2 can be in a Set Mode or FreeFloat Mode. In one embodiment or in combination with any other mentionedembodiments, the COT2 is in a Free Float Mode and the hydrocarbon massflow rate of the combined cracker stream in step (b) is higher than thehydrocarbon mass flow rate of the cracker stream in step (a). In oneembodiment or in combination with any mentioned embodiments, the COT2 isin a Set Mode.

In one embodiment or in combination with any mentioned embodiments,there is provided a method for making one or more olefins by:

-   -   (a) cracking a cracker stream in a cracking unit at a first coil        outlet temperature (COT1);    -   (b) subsequent to step (a), adding a stream comprising a recycle        content pyrolysis oil composition (r-pyoil) to said cracker        stream to form a combined cracker stream; and    -   (c) cracking said combined cracker stream in said cracking unit        at a second coil outlet temperature (COT2), wherein said second        coil outlet temperature is higher than the first coil outlet        temperature.

The COT2 can be at least 5, 8, 10, 12, 15, 18, 20, 25, 30, 35, 40, 45,50° C. and/or not more than about not more than 150, 140, 130, 125, 120,110, 105, 100, 90, 80, 75, 70, or 65° C. higher than COT1.

In one embodiment or in combination with any other mentionedembodiments, r-pyoil is added to the inlet of at least one coil, or atleast two coils, or at least 50%, or at least 75%, or all of the coils,to form at least one combined cracker stream, or at least two combinedcracker streams, or at least the same number of combined crackersstreams as coils accepting a feed of r-pyoil. At least one, or at leasttwo of the combined cracker streams, or at least all of the r-pyoil fedcoils can have a COT2 that is higher than their respective COT1. In oneembodiment or in combination with any mentioned embodiments, at leastone, or at least two coils, or at least 50%, or at least 75% of thecoils within said cracking furnace contain only non-recycle contentcracker feed, with at least one of the coils in the cracking furnacebeing fed with r-pyoil, and the coil or at least some of multiple coilsfed with r-pyoil having a COT2 higher than their respective COT1.

In one embodiment or in combination with any mentioned embodiments, thehydrocarbon mass flow rate of the combined stream in step (b) issubstantially the same as or lower than the hydrocarbon mass flow rateof the cracker stream in step (a). By substantially the same is meantnot more than a 2% difference, or not more than a 1% difference, or notmore than a 0.25% difference. When the hydrocarbon mass flow rate of thecombined cracker stream in step (b) is substantially the same as orlower than the hydrocarbon mass flow rate of the cracker stream (a), andthe COT2 is allowed to operate in a Free Float Mode (where at least 1 ofthe tubes contains non-recycle content cracker stream), the COT2 on ther-pyoil containing coil can rise relative to COT1. This is the case eventhough the pyoil, having a larger number average molecular weightcompared to the cracker stream, requires less energy to crack. Withoutbeing bound to a theory, it is believed that one or a combination offactors contribute to the temperature rise, including the following:

-   -   a. Lower heat energy is required to crack pyoil in the combined        stream; or    -   b. The occurrence of exothermic reactions among cracked products        of pyoil, such as diels-alder reactions.

This effect can be seen when the other process variables are constant,such as the firebox fuel rate, dilution steam ratio, location of feeds,and composition of the cracker feed.

In one embodiment or in combination with any mentioned embodiments, theCOT2 can be set or fixed to a higher temperature than COT1 (the SetMode). This is more applicable when the hydrocarbon mass flow rate ofthe combined cracker stream is higher than the hydrocarbon mass flowrate of the cracker stream which would otherwise lower the COT2. Thehigher second coil outlet temperature (COT2) can contribute to anincreased severity and a decreased output of unconverted lighter crackerfeed (e.g. C₂-C₄ feed), which can assist with downstream capacityrestricted fractionation columns.

In one embodiment or in combination with any mentioned embodiments,whether the COT2 is higher or lower than COT1, the cracker feedcompositions are the same when a comparison is made between COT2 with aCOT1. Desirably, the cracker feed composition in step (a) is the samecracker composition as used to make the combined cracker stream in step(b). Optionally, the cracker composition feed in step (a) iscontinuously fed to the cracker unit, and the addition of pyoil in step(b) is to the continuous cracker feed in step (a). Optionally, the feedof pyoil to the cracker feed is continuous for at least 1 day, or atleast 2 days, or at least 3 days, or at least 1 week, or at least 2weeks, or at least 1 month, or at least 3 months, or at least 6 monthsor at least 1 year.

The amount of raising or lowering the cracker feed in step (b) in any ofthe mentioned embodiments can be at least 2%, or at least 5%, or atleast 8%, or at least 10%. In one embodiment or in combination with anymentioned embodiments, the amount of lowering the cracker feed in step(b) can be an amount that corresponds to the addition of pyoil byweight. In one embodiment or in combination with any mentionedembodiments, the mass flow of the combined cracker feed is at least 1%,or at least 5%, or at least 8%, or at least 10% higher than thehydrocarbon mass flow rate of the cracker feed in step (a).

In any or all of the mentioned embodiments, the cracker feed or combinedcracker feed mass flows and COT relationships and measurements aresatisfied if any one coil in the furnace satisfies the statedrelationships but can also be present in multiple tubes depending on howthe pyoil is fed and distributed.

In an embodiment or in combination with any of the embodiments mentionedherein, the burners in the radiant zone provide an average heat fluxinto the coil in the range of from 60 to 160 kW/m2 or 70 to 145 kW/m2 or75 to 130 kW/m2. The maximum (hottest) coil surface temperature is inthe range of 1035 to 1150° C. or 1060 to 1180° C. The pressure at theinlet of the furnace coil in the radiant section is in the range of 1.5to 8 bar absolute (bara), or 2.5 to 7 bara, while the outlet pressure ofthe furnace coil in the radiant section is in the range of from 1.03 to2.75 bara, or 1.03 to 2.06 bara. The pressure drop across the furnacecoil in the radiant section can be from 1.5 to 5 bara, or 1.75 to 3.5bara, or 1.5 to 3 bara, or 1.5 to 3.5 bara.

In an embodiment or in combination with any of the embodiments mentionedherein, the yield of olefin—ethylene, propylene, butadiene, orcombinations thereof—can be at least 15, or at least 20, or at least 25,or at least 30, or at least 35, or at least 40, or at least 45, or atleast 50, or at least 55, or at least 60, or at least 65, or at least70, or at least 75, or at least 80, in each case percent. As usedherein, the term “yield” refers to the mass of product/mass of feedstockx 100%. The olefin-containing effluent stream comprises at least about30, or at least 40, or at least 50, or at least 60, or at least 70, orat least 75, or at least 80, or at least 85, or at least 90, or at least95, or at least 97, or at least 99, in each case weight percent ofethylene, propylene, or ethylene and propylene, based on the totalweight of the effluent stream.

In an embodiment or in combination with one or more embodimentsmentioned herein, the olefin-containing effluent stream 670 can compriseC₂ to C₄ olefins, or propylene, or ethylene, or C₄ olefins, in an amountof at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75,80, 85, or 90 weight percent, based on the weight of theolefin-containing effluent. The stream may comprise predominantlyethylene, predominantly propylene, or predominantly ethylene andpropylene, based on the olefins in the olefin-containing effluent, orbased on the weight of the C₁-C₅ hydrocarbons in the olefin-containingeffluent, or based on the weight of the olefin-containing effluentstream. The weight ratio of ethylene-to-propylene in theolefin-containing effluent stream can be at least about 0.2:1, 0.3:1,0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1, 1.1:1, 1.2:1, 1.3:1,1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1, or 2:1 and/or not more than3:1, 2.9:1, 2.8:1, 2.7:1, 2.5:1, 2.3:1, 2.2:1, 2.1:1, 2:1, 1.7:1, 1.5:1,or 1.25:1. In an embodiment or in combination with one or moreembodiments mentioned herein, the olefin-containing effluent stream canhave a ratio of propylene:ethylene that is higher than thepropylene:ethylene ratio of an effluent stream obtained by cracking thesame cracker feed but without r-pyoil at equivalent dilution steamratios, feed locations, cracker feed compositions (other than ther-pyoil), and allowing the coils fed with r-pyoil to be in the FloatMode, or if all coils in a furnace are fed with r-pyoil, then at thesame temperature prior to feeding r-pyoil. As discussed above, this ispossible when the mass flow of the cracker feed remains substantiallythe same resulting in a higher hydrocarbon mass flow rate of thecombined cracker stream when r-pyoil is added relative to the originalfeed of the cracker stream.

The olefin-containing effluent stream can have a ratio ofpropylene:ethylene that is at least 1% higher, or at least 2% higher, orat least 3% higher, or at least 4% higher, or at least 5% higher or atleast 7% higher or at least 10% higher or at least 12% higher or atleast 15% higher or at least 17% higher or at least 20% higher than thepropylene:ethylene ratio of an effluent stream obtained by cracking thesame cracker feed but without r-pyoil. Alternatively or in addition, theolefin-containing effluent stream can have a ratio of propylene:ethylenethat is up to 50% higher, or up to 45% higher, or up to 40% higher, orup to 35% higher, or up to 25% higher, or up to 20% higher than thepropylene:ethylene ratio of an effluent stream obtained by cracking thesame cracker feed but without r-pyoil, in each case determined as:

${\%{increase}} = {\frac{{Er} - E}{E} \times 100}$

-   -   where E is the propylene:ethylene ratio by wt. % in the cracker        effluent made without r-pyoil; and    -   E_(r) is the propylene:ethylene ratio by wt. % in the cracker        effluent made with r-pyoil.

In an embodiment or in combination with any of the embodiments mentionedherein, the amount of ethylene and propylene can remain substantiallyunchanged or increased in the cracked olefin-containing effluent streamrelative to an effluent stream without r-pyoil. It is surprising that aliquid r-pyoil can be fed to a gas fed furnace that accepts and cracks apredominant C₂-C₄ composition and obtain an olefin-containing effluentstream that can remain substantially unchanged or improved in certaincases relative to a C₂-C₄ cracker feed without r-pyoil. The heavymolecular weight of r-pyoil could have predominately contributed to theformation of aromatics and participate in the formation of olefins(ethylene and propylene in particular) in only a minor amount. However,we have found that the combined weight percent of ethylene andpropylene, and even the output, does not significantly drop, and in manycases stays the same or can increase when r-pyoil is added to a crackerfeed to form a combined cracker feed at the same hydrocarbon mass flowrates relative to a cracker feed without r-pyoil. The olefin-containingeffluent stream can have a total wt. % of propylene and ethylene that isthe same as or higher than the propylene and ethylene content of aneffluent stream obtained by cracking the same cracker feed but withoutr-pyoil by at least 0.5%, or at least 1%, or at least 2%, or at least2.5%, determined as:

${\%{increase}} = {\frac{{Er} - E}{E} \times 100}$

-   -   where E is the combined wt. % of propylene and ethylene content        in the cracker effluent made without r-pyoil; and    -   E_(r) is the combined wt. % of propylene and ethylene content in        the cracker effluent made with r-pyoil.

In an embodiment or in combination with one or more embodimentsmentioned herein, the wt % of propylene can improve in anolefin-containing effluent stream when the dilution steam ratio (ratioof steam:hydrocarbons by weight) is above 0.3, or above 0.35, or atleast 0.4. The increase in the wt. % of propylene when the dilutionsteam ratio is at least 0.3, or at least 0.35, or at least 0.4 can be upto 0.25 wt. %, or up to 0.4 wt. %, or up to 0.5 wt. %, or up to 0.7 wt.%, or up to 1 wt. %, or up to 1.5 wt. %, or up to 2 wt. %, where theincrease is measured as the simple difference between the wt. % ofpropylene between an olefin-containing effluent stream made with r-pyoilat a dilution steam ratio of 0.2 and an olefin-containing effluentstream made with r-pyoil at a dilution steam ratio of at least 0.3, allother conditions being the same.

When the dilution steam ratio is increased as noted above, the ratio ofpropylene:ethylene can also increase, or can be at least 1% higher, orat least 2% higher, or at least 3% higher, or at least 4% higher, or atleast 5% higher or at least 7% higher or at least 10% higher or at least12% higher or at least 15% higher or at least 17% higher or at least 20%higher than the propylene:ethylene ratio of an olefin-containingeffluent stream made with r-pyoil at a dilution steam ratio of 0.2.

In an embodiment or in combination with one or more embodimentsmentioned herein, when the dilution steam ratio is increased, theolefin-containing effluent stream can have a reduced wt. % of methane,when measured relative to an olefin-containing effluent stream at adilution steam ratio of 0.2. The wt. % of methane in theolefin-containing effluent stream can be reduced by at least 0.25 wt. %,or by at least 0.5 wt. %, or by at least 0.75 wt. %, or by at least 1wt. %, or by at least 1.25 wt. %, or by at least 1.5 wt. %, measured asthe absolute value difference in wt. % between the olefin-containingeffluent stream at a dilution steam ratio of 0.2 and at the higherdilution steam ratio value.

In an embodiment or in combination with one or more embodimentsmentioned herein, the amount of unconverted products in theolefin-containing effluent is decreased, when measured relative to acracker feed that does not contain r-pyoil and all other conditionsbeing the same, including hydrocarbon mass flow rate. For example, theamount of propane and/or ethane can be decreased by addition of r-pyoil.This can be advantageous to decrease the mass flow of the recycle loopto thereby (a) decrease cryogenic energy costs and/or (b) potentiallyincrease capacity on the plant if the plant is already capacityconstrained. Further it can debottleneck the propylene fractionator ifit is already to its capacity limit. The amount of unconverted productsin the olefin containing effluent can decrease by at least 2%, or atleast 5%, or at least 8%, or at least 10%, or at least 13%, or at least15%, or at least 18%, or at least 20%.

In an embodiment or in combination with one or more embodimentsmentioned herein, the amount of unconverted products (e.g. combinedpropane and ethane amount) in the olefin-containing effluent isdecreased while the combined output of ethylene and propylene does notdrop and is even improved, when measured relative to a cracker feed thatdoes not contain r-pyoil. Optionally, all other conditions are the sameincluding the hydrocarbon mass flow rate and with respect totemperature, where the fuel feed rate to heat the burners to thenon-recycle content cracker fed coils remains unchanged, or optionallywhen the fuel feed rate to all coils in the furnace remains unchanged.Alternatively, the same relationship can hold true on a wt. % basisrather than an output basis.

For example, the combined amount (either or both of output or wt. %) ofpropane and ethane in the olefin containing effluent can decrease by atleast 2%, or at least 5%, or at least 8%, or at least 10%, or at least13,%, or at least 15%, or at least 18%, or at least 20%, and in eachcase up to 40% or up to 35% or up to 30%, in each case without adecrease in the combined amount of ethylene and propylene, and even canaccompany an increase in the combined amount of ethylene and propylene.In another example, the amount of propane in the olefin containingeffluent can decrease by at least 2%, or at least 5%, or at least 8%, orat least 10%, or at least 13,%, or at least 15%, or at least 18%, or atleast 20%, and in each case up to 40% or up to 35% or up to 30%, in eachcase without a decrease in the combined amount of ethylene andpropylene, and even can accompany an increase in the combined amount ofethylene and propylene. In any one of these embodiments, the crackerfeed (other than r-pyoil and as fed to the inlet of the convection zone)can be predominately propane by moles, or at least 90 mole % propane, orat least 95 mole % propane, or at least 96 mole % propane, or at least98 mole % propane; or the fresh supply of cracker feed can be at leastHD5 quality propane.

In an embodiment or in combination with one or more embodimentsmentioned herein, the ratio of propane:(ethylene and propylene) in theolefin-containing effluent can decrease with the addition of r-pyoil tothe cracker feed when measured relative to the same cracker feed withoutpyoil and all other conditions being the same, measured either as wt. %or output. The ratio of propane:(ethylene and propylene combined) in theolefin-containing effluent can be not more than 0.50:1, or less than0.50:1, or not more than 0.48:1, or not more than 0.46:1, or no morethan 0.43:1, or no more than 0.40:1, or no more than 0.38:1, or no morethan 0.35:1, or no more than 0.33:1, or no more than 0.30:1 The lowratios indicate that a high amount of ethylene+propylene can be achievedor maintained with a corresponding drop in unconverted products such aspropane.

In an embodiment or in combination with one or more embodimentsmentioned herein, the amount of C₆₊ products in the olefin-containingeffluent can be increased, if such products are desired such as for aBTX stream to make derivates thereof, when r-pyoil and steam are feddownstream of the inlet to the convection box, or when one or both ofr-pyoil and steam are fed at the cross-over location. The amount of C₆₊products in the olefin-containing effluent can be increased by 5%, or by10%, or by 15%, or by 20%, or by 30% when r-pyoil and steam are feddownstream of the inlet to the convection box, when measured againstfeeding r-pyoil at the inlet to the convection box, all other conditionsbeing the same. The % increase can be calculated as:

${\%{increase}} = {\frac{{Ei} - {Ed1}}{Ei} \times 100}$

-   -   where    -   E_(i) is the C₆₊ content in the olefin-containing cracker        effluent made by introducing r-pyoil at the inlet of the        convection box; and    -   E_(d) is the C₆₊ content in the olefin-containing cracker        effluent made by introducing r-pyoil and steam downstream of the        inlet of the convection box.

In an embodiment or in combination with any of the embodiments mentionedherein, the cracked olefin-containing effluent stream may includerelatively minor amounts of aromatics and other heavy components. Forexample, the olefin-containing effluent stream may include at least 0.5,1, 2, or 2.5 weight percent and/or not more than about 20, 19, 18, 17,16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 weight percentof aromatics, based on the total weight of the stream. We have foundthat the level of C₆₊ species in the olefin-containing effluent can benot more than 5 wt. %, or not more than 4 wt. %, or not more than 3.5wt. %, or not more than 3 wt. %, or not more than 2.8 wt. %, or not morethan 2.5 wt. %. The C₆₊ species includes all aromatics, as well as allparaffins and cyclic compounds having a carbon number of 6 or more. Asused throughout, the mention of amounts of aromatics can be representedby amounts of C₆₊ species since the amount of aromatics would not exceedthe amount of C₆₊ species.

The olefin-containing effluent may have an olefin-to-aromatic ratio, byweight %, of at least 2:1, 3.1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1,11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1, 20:1, 21:1, 22:1,23:1, 24:1, 25:1, 26:1, 27:1, 28:1, 29:1, or 30:1 and/or not more than100:1, 90:1, 85:1, 80:1, 75:1, 70:1, 65:1, 60:1, 55:1, 50:1, 45:1, 40:1,35:1, 30:1, 25:1, 20:1, 15:1, 10:1, or 5:1. As used herein,“olefin-to-aromatic ratio” is the ratio of total weight of C₂ and C₃olefins to the total weight of aromatics, as defined previously. In anembodiment or in combination with any of the embodiments mentionedherein, the effluent stream can have an olefin-to-aromatic ratio of atleast 2.5:1, 2.75:1, 3.5:1, 4.5:1, 5.5:1, 6.5:1, 7.5:1, 8.5:1, 9.5:1,10.5:1, 11.5:1, 12.5:1, or 13:5:1.

The olefin-containing effluent may have an olefin:C₆₊ ratio, by weight%, of at least 8.5:1, or at least 9.5:1, or at least 10:1, or at least10.5:1, or at least 12:1, or at least 13:1, or at least 15:1, or atleast 17:1, or at least 19:1, or at least 20:1, or at least 25:1, orleast 28:1, or at least 30:1. In addition or in the alternative, theolefin-containing effluent may have an olefin:C₆₊ ratio of up to 40:1,or up to 35:1, or up to 30:1, or up to 25:1, or up to 23:1. As usedherein, “olefin-to-aromatic ratio” is the ratio of total weight of C₂and C₃ olefins to the total weight of aromatics, as defined previously.

Additionally, or in the alternative, the olefin-containing effluentstream can have an olefin-to-C6+ ratio of at least about 1.5:1, 1.75:1,2:1, 2.25:1, 2.5:1, 2.75:1, 3:1, 3.25:1, 3.5:1, 3.75:1, 4:1, 4.25:1,4.5:1, 4.75:1, 5:1, 5.25:1, 5.5:1, 5.75:1, 6:1, 6.25:1, 6.5:1, 6.75:1,7:1, 7.25:1, 7.5:1, 7.75:1, 8:1, 8.25:1, 8.5:1, 8.75:1, 9:1, 9.5:1,10:1, 10.5:1, 12:1, 13:1, 15:1, 17:1, 19:1, 20:1, 25:1, 28:1, or 30:1.

In an embodiment or in combination with any of the embodiments mentionedherein, the olefin:aromatic ratio decreases with an increase in theamount of r-pyoil added to the cracker feed. Since r-pyoil cracks at alower temperature, it will crack earlier than propane or ethane, andtherefore has more time to react to make other products such asaromatics. Although the aromatic content in the olefin-containingeffluent increases with an increasing amount of pyoil, the amount ofaromatics produced is remarkably low as noted above.

The olefin-containing composition may also include trace amounts ofaromatics. For example, the composition may have a benzene content of atleast 0.25, 0.3, 0.4, 0.5 weight percent and/or not more than about 2,1.7, 1.6, 1.5 weight percent. Additionally, or in the alternative, thecomposition may have a toluene content of at least 0.005, 0.010, 0.015,or 0.020 and/or not more than 0.5, 0.4, 0.3, or 0.2 weight percent. Bothpercentages are based on the total weight of the composition.Alternatively, or in addition, the effluent can have a benzene contentof at least 0.2, 0.3, 0.4, 0.5, or 0.55 and/or not more than about 2,1.9, 1.8, 1.7, or 1.6 weight percent and/or a toluene content of atleast 0.01, 0.05, or 0.10 and/or not more than 0.5, 0.4, 0.3, or 0.2weight percent.

In an embodiment or in combination with any of the embodiments mentionedherein, the olefin-containing effluent withdrawn from a cracking furnacewhich has cracked a composition comprising r-pyoil may include anelevated amount of one or more compounds or by-products not found inolefin-containing effluent streams formed by processing conventionalcracker feed. For example, the cracker effluent formed by crackingr-pyoil (r-olefin) may include elevated amounts of 1,3-butadiene,1,3-cyclopentadiene, dicyclopentadiene, or a combination of thesecomponents. In an embodiment or in combination with any of theembodiments mentioned herein, the total amount (by weight) of thesecomponents may be at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55,60, 65, 70, 75, 80, or 85 percent higher than an identical cracker feedstream processed under the same conditions and at the same mass feedrate, but without r-pyoil. The total amount (by weight) of 1,3-butadienemay be at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70,75, 80, or 85 percent higher than an identical cracker feed streamprocessed under the same conditions and at the same mass feed rate, butwithout r-pyoil. The total amount (by weight) of 1,3-cyclopentadiene maybe at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75,80, or 85 percent higher than an identical cracker feed stream processedunder the same conditions and at the same mass feed rate, but withoutr-pyoil. The total amount (by weight) of dicyclopentadiene may be atleast 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, or85 percent higher than an identical cracker feed stream processed underthe same conditions and at the same mass feed rate, but without r-pyoil.The percent difference is calculated by dividing the difference inweight percent of one or more of the above components in the r-pyoil andconventional streams by the amount (in weight percent) of the componentin the conventional stream, or:

${\%{increase}} = {\frac{{Er} - E}{E} \times 100}$

-   -   where E is the wt. % of the component in the cracker effluent        made without r-pyoil; and    -   E_(r) is the wt. % of the component in the cracker effluent made        with r-pyoil.

In an embodiment or in combination with any of the embodiments mentionedherein, the olefin-containing effluent stream may comprise acetylene.The amount of acetylene can be at least 2000 ppm, at least 5000 ppm, atleast 8000 ppm, or at least 10,000 ppm based on the total weight of theeffluent stream from the furnace. It may also be not more than 50,000ppm, not more than 40,000 ppm, not more than 30,000 ppm, or not morethan 25,000 ppm, or not more than 10,000 ppm, or not more than 6,000ppm, or not more than 5000 ppm.

In an embodiment or in combination with any of the embodiments mentionedherein, the olefin-containing effluent stream may comprise methylacetylene and propadiene (MAPD). The amount of MAPD may be at least 2ppm, at least 5 ppm, at least 10 ppm, at least 20 pm, at least 50 ppm,at least 100 ppm, at least 500 ppm, at least 1000 ppm, at least 5000ppm, or at least 10,000 ppm, based on the total weight of the effluentstream. It may also be not more than 50,000 ppm, not more than 40,000ppm, or not more than 30,000 ppm, or not more than 10,000 ppm, or notmore than 6,000 ppm, or not more than 5,000 ppm.

In an embodiment or in combination with any of the embodiments mentionedherein, the olefin-containing effluent stream may comprise low or noamounts of carbon dioxide. The olefin-containing effluent stream canhave an amount, in wt. %, of carbon dioxide that is not more than theamount of carbon dioxide in an effluent stream obtained by cracking thesame cracker feed but without r-pyoil at equivalent conditions, or anamount this is not higher than 5%, or not higher than 2% of the amountof carbon dioxide, in wt. %, or the same amount as a comparativeeffluent stream without r-pyoil. Alternatively or in addition, theolefin-containing effluent stream can have an amount of carbon dioxidethat is not more than 1000 ppm, or not more than 500 ppm, or not morethan 100 ppm, or not more than 80 ppm, or not more than 50 ppm, or notmore than 25 ppm, or not more than 10 ppm, or not more than 5 ppm.

Turning now to FIG. 9, a block diagram illustrating the main elements ofthe furnace effluent treatment section are shown.

As shown in FIG. 9, the olefin-containing effluent stream from thecracking furnace 700, which includes recycle content) is cooled rapidly(e.g., quenched) in a transfer line exchange (“TLE”) 680 as shown inFIG. 8 in order to prevent production of large amounts of undesirableby-products and to minimize fouling in downstream equipment, and also togenerate steam. In an embodiment or in combination with any of theembodiments mentioned herein, the temperature of ther-composition-containing effluent from the furnace can be reduced by 35to 485° C., 35 to 375° C., or 90 to 550° C. to a temperature of 500 to760° C. The cooling step is performed immediately after the effluentstream leaves the furnace such as, for example, within 1 to 30, 5 to 20,or 5 to 15 milliseconds. In an embodiment or in combination with any ofthe embodiments mentioned herein, the quenching step is performed in aquench zone 710 via indirect heat exchange with high-pressure water orsteam in a heat exchanger (sometimes called a transfer line exchanger asshown in FIG. 5 as TLE 340 and FIG. 8 as TLE 680), while, in otherembodiments, the quench step is carried out by directly contacting theeffluent with a quench liquid 712 (as generally shown in FIG. 9). Thetemperature of the quench liquid can be at least 65, or at least 80, orat least 90, or at least 100, in each case ° C. and/or not more than210, or not more than 180, or not more than 165, or not more than 150,or not more than 135, in each case ° C. When a quench liquid is used,the contacting may occur in a quench tower and a liquid stream may beremoved from the quench tower comprising gasoline and other similarboiling-range hydrocarbon components. In some cases, quench liquid maybe used when the cracker feed is predominantly liquid, and a heatexchanger may be used when the cracker feed is predominantly vapor.

The resulting cooled effluent stream is then vapor liquid separated andthe vapor is compressed in a compression zone 720, such as in a gascompressor having, for example, between 1 and 5 compression stages withoptional inter-stage cooling and liquid removal. The pressure of the gasstream at the outlet of the first set of compression stages is in therange of from 7 to 20 bar gauge (barg), 8.5 to 18 psig (0.6˜1.3 barg),or 9.5 to 14 barg.

The resulting compressed stream is then treated in an acid gas removalzone 722 for removal of acid gases, including CO, CO₂, and H₂S bycontact with an acid gas removal agent. Examples of acid gas removalagents can include, but are not limited to, caustic and various types ofamines. In an embodiment or in combination with any of the embodimentsmentioned herein, a single contactor may be used, while, in otherembodiments, a dual column absorber-stripper configuration may beemployed.

The treated compressed olefin-containing stream may then be furthercompressed in another compression zone 724 via a compressor, optionallywith inter-stage cooling and liquid separation. The resulting compressedstream, which has a pressure in the range of 20 to 50 barg, 25 to 45barg, or 30 to 40 barg. Any suitable moisture removal method can be usedincluding, for example, molecular sieves or other similar process to drythe gas in a drying zone 726. The resulting stream 730 may then bepassed to the fractionation section, wherein the olefins and othercomponents may be separated in to various high-purity product orintermediate streams.

Turning now to FIG. 10, a schematic depiction of the main steps of thefractionation section is provided. In an embodiment or in combinationwith any of the embodiments mentioned herein, the initial column of thefractionation train may not be a demethanizer 810, but may be adeethanizer 820, a depropanizer 840, or any other type of column. Asused herein, the term “demethanizer,” refers to a column whose light keyis methane. Similarly, “deethanizer,” and “depropanizer,” refer tocolumns with ethane and propane as the light key component,respectively.

As shown in FIG. 10, a feed stream 870 from the quench section mayintroduced into a demethanizer (or other) column 810, wherein themethane and lighter (CO, CO₂, H₂) components 812 are separated from theethane and heavier components 814. The demethanizer is operated at atemperature of at least −145, or at least −142, or at least −140, or atleast −135, in each case ° C. and/or not more than −120, −125, −130,−135° C. The bottoms stream 814 from the demethanizer column, whichincludes at least 50, or at least 55, or at least 60, or at least 65, orat least 70, or at least 75, or at least 80, or at least 85, or at least90, or at least 95 or at least 99, in each case percent of the totalamount of ethane and heavier components introduced into the column, isthen introduced into a deethanizer column 820, wherein the C₂ andlighter components 816 are separated from the C3 and heavier components818 by fractional distillation. The de-ethanizer 820 can be operatedwith an overhead temperature of at least −35, or at least −30, or atleast −25, or at least −20, in each case ° C. and/or not more than −5,−10, −10, −20° C., and an overhead pressure of at least 3, or at least5, or at least 7, or at least 8, or at least 10, in each case bargand/or not more than 20, or not more than 18, or not more than 17, ornot more than 15, or not more than 14, or not more than 13, in each casebarg. The deethanizer column 820 recovers at least 60, or at least 65,or at least 70, or at least 75, or at least 80, or at least 85, or atleast 90, or at least 95, or at least 97, or at least 99, in each casepercent of the total amount of C₂ and lighter components introduced intothe column in the overhead stream. In an embodiment or in combinationwith any of the embodiments mentioned herein, the overhead stream 816removed from the deethanizer column comprises at least 50, or at least55, or at least 60, or at least 65, or at least 70, or at least 75, orat least 80, or at least 85, or at least 90, or at least 95, in eachcase weight percent of ethane and ethylene, based on the total weight ofthe overhead stream.

As shown in FIG. 10, the C₂ and lighter overhead stream 816 from thedeethanizer 820 is further separated in an ethane-ethylene fractionatorcolumn (ethylene fractionator) 830. In the ethane-ethylene fractionatorcolumn 830, an ethylene and lighter component stream 822 can bewithdrawn from the overhead of the column 830 or as a side stream fromthe top ½ of the column, while the ethane and any residual heaviercomponents are removed in the bottoms stream 824. The ethylenefractionator 830 may be operated at an overhead temperature of at least−45, or at least −40, or at least −35, or at least −30, or at least −25,or at least −20, in each case ° C. and/or not more than −15, or not morethan −20, or not more than −25, in each case ° C., and an overheadpressure of at least 10, or at least 12, or at least 15, in each casebarg and/or not more than 25, 22, 20 barg. The overhead stream 822,which is enriched in ethylene, can include at least 70, or at least 75,or at least 80, or at least 85, or at least 90, or at least 95, or atleast 97, or at least 98, or at least 99, in each case weight percentethylene, based on the total weight of the stream and may be sent todownstream processing unit for further processing, storage, or sale. Theoverhead ethylene stream 822 produced during the cracking of a crackerfeedstock containing r-pyoil is a r-ethylene composition or stream. Inan embodiment or in combination with any of the embodiments mentionedherein, the r-ethylene stream may be used to make one or morepetrochemicals.

The bottoms stream from the ethane-ethylene fractionator 824 may includeat least 40, or at least 45, or at least 50, or at least 55, or at least60, or at least 65, or at least 70, or at least 75, or at least 80, orat least 85, or at least 90, or at least 95, or at least 98, in eachcase weight percent ethane, based on the total weight of the bottomsstream. All or a portion of the recovered ethane may be recycled to thecracker furnace as additional feedstock, alone or in combination withthe r-pyoil containing feed stream, as discussed previously.

The liquid bottoms stream 818 withdrawn from the deethanizer column,which may be enriched in C3 and heavier components, may be separated ina depropanizer 840, as shown in FIG. 10. In the depropanizer 840, C3 andlighter components are removed as an overhead vapor stream 826, while C4and heavier components may exit the column in the liquid bottoms 828.The depropanizer 840 can be operated with an overhead temperature of atleast 20, or at least 35, or at least 40, in each case ° C. and/or notmore than 70, 65, 60, 55° C., and an overhead pressure of at least 10,or at least 12, or at least 15, in each case barg and/or not more than20, or not more than 17, or not more than 15, in each case barg. Thedepropanizer column 840 recovers at least 60, or at least 65, or atleast 70, or at least 75, or at least 80, or at least 85, or at least90, or at least 95, or at least 97, or at least 99, in each case percentof the total amount of C3 and lighter components introduced into thecolumn in the overhead stream 826. In an embodiment or in combinationwith any of the embodiments mentioned herein, the overhead stream 826removed from the depropanizer column 840 comprises at least or at least50, or at least 55, or at least 60, or at least 65, or at least 70, orat least 75, or at least 80, or at least 85, or at least 90, or at least95, or at least 98, in each case weight percent of propane andpropylene, based on the total weight of the overhead stream 826.

The overhead stream 826 from the depropanizer 840 are introduced into apropane-propylene fractionator (propylene fractionator) 860, wherein thepropylene and any lighter components are removed in the overhead stream832, while the propane and any heavier components exit the column in thebottoms stream 834. The propylene fractionator 860 may be operated at anoverhead temperature of at least 20, or at least 25, or at least 30, orat least 35, in each case ° C. and/or not more than 55, 50, 45, 40° C.,and an overhead pressure of at least 12, or at least 15, or at least 17,or at least 20, in each case barg and/or not more than 20, or not morethan 17, or not more than 15, or not more than 12, in each case barg.The overhead stream 860, which is enriched in propylene, can include atleast 70, or at least 75, or at least 80, or at least 85, or at least90, or at least 95, or at least 97, or at least 98, or at least 99, ineach case weight percent propylene, based on the total weight of thestream and may be sent to downstream processing unit for furtherprocessing, storage, or sale. The overhead propylene stream producedduring the cracking of a cracker feedstock containing r-pyoil is ar-propylene composition or stream. In an embodiment or in combinationwith any of the embodiments mentioned herein, the stream may be used tomake one or more petrochemicals.

The bottoms stream 834 from the propane-propylene fractionator 860 mayinclude at least 40, or at least 45, or at least 50, or at least 55, orat least 60, or at least 65, or at least 70, or at least 75, or at least80, or at least 85, or at least 90, or at least 95, or at least 98, ineach case weight percent propane, based on the total weight of thebottoms stream 834. All or a portion of the recovered propane may berecycled to the cracker furnace as additional feedstock, alone or incombination with r-pyoil, as discussed previously.

Referring again to FIG. 10, the bottoms stream 828 from the depropanizercolumn 840 may be sent to a debutanizer column 850 for separating C4components, including butenes, butanes and butadienes, from C5+components. The debutanizer can be operated with an overhead temperatureof at least 20, or at least 25, or at least 30, or at least 35, or atleast 40, in each case ° C. and/or not more than 60, or not more than65, or not more than 60, or not more than 55, or not more than 50, ineach case ° C. and an overhead pressure of at least 2, or at least 3, orat least 4, or at least 5, in each case barg and/or not more than 8, ornot more than 6, or not more than 4, or not more than 2, in each casebarg. The debutanizer column recovers at least 60, or at least 65, or atleast 70, or at least 75, or at least 80, or at least 85, or at least90, or at least 95, or at least 97, or at least 99, in each case percentof the total amount of C4 and lighter components introduced into thecolumn in the overhead stream 836. In an embodiment or in combinationwith any of the embodiments mentioned herein, the overhead stream 836removed from the debutanizer column comprises at least 30, or at least35, or at least 40, or at least 45, or at least 50, or at least 55, orat least 60, or at least 65, or at least 70, or at least 75, or at least80, or at least 85, or at least 90, or at least 95, in each case weightpercent of butadiene, based on the total weight of the overhead stream.The overhead stream 836 produced during the cracking of a crackerfeedstock containing r-pyoil is a r-butadiene composition or stream. Thebottoms stream 838 from the debutanizer includes mainly C5 and heaviercomponents, in an amount of at least 50, or at least 60, or at least 70,or at least 80, or at least 90, or at least 95 weight percent, based onthe total weight of the stream. The debutanizer bottoms stream 838 maybe sent for further separation, processing, storage, sale or use.

The overhead stream 836 from the debutanizer, or the C4s, can besubjected to any conventional separation methods such as extraction ordistillation processes to recover a more concentrated stream ofbutadiene.

EXAMPLES r-Pyoil Examples 1-4

Table 1 shows the composition of r-pyoil samples by gas chromatography.The r-pyoil samples produced the material from waste high and lowdensity polyethylene, polypropylene, and polystyrene. Sample 4 was alab-distilled sample in which hydrocarbons greater than C21 wereremoved. The boiling point curves of these materials are shown in FIGS.13-16.

TABLE 1 Gas Chromatography Analysis of r-Pyoil Examples r-Pyoil FeedExamples Components 1 2 3 4 Propene 0.00 0.00 0.00 0.00 Propane 0.000.19 0.20 0.00 1,3-Butadiene 0.00 0.93 0.99 0.31 Pentene 0.16 0.37 0.390.32 Pentane 1.81 3.21 3.34 3.05 1,3-cyclopentadiene 0.00 0.00 0.00 0.002-methyl-Pentene 1.53 2.11 2.16 2.25 2-methyl-Pentane 2.04 2.44 2.483.03 Hexane 1.37 1.80 1.83 2.10 2-methyl-1,3-cyclopentadiene 0.00 0.000.00 0.00 1-methyl-1,3-cyclopentadiene 0.00 0.00 0.00 0.00 2,4dimethylpentene 0.32 0.18 0.18 0.14 Benzene 0.00 0.16 0.16 0.005-methyl-1,3-cyclopentadiene 0.00 0.17 0.17 0.20 Heptene 1.08 1.15 1.151.55 Heptane 2.51 0.17 2.89 3.61 Toluene 0.58 1.05 1.09 0.844-methylheptane 1.50 1.67 1.68 1.99 Octene 1.37 1.35 1.37 1.88 Octane2.56 2.72 2.78 3.40 2,4-dimethylheptene 1.25 1.54 1.55 1.602,4-dimethylheptane 5.08 4.01 4.05 6.40 Ethylbenzene 1.85 3.10 3.12 2.52m,p-xylene 0.73 0.69 0.24 0.90 Styrene 0.40 0.13 1.13 0.53 o-xylene 0.120.36 0.00 0.00 Nonane 2.66 2.81 2.84 3.47 Nonene 1.12 0.00 0.00 1.65MW140 2.00 1.76 1.75 2.50 Cumene 0.56 0.96 0.97 0.73Decene/methylstyrene 1.29 1.17 1.18 1.60 Decane 3.14 3.23 3.25 3.90Unknown 1 0.68 0.71 0.72 0.80 Indene 0.18 0.20 0.21 0.22 Indane 0.230.34 0.26 0.26 C11 Alkene 1.50 1.32 1.33 1.77 C11 Alkane 3.30 3.30 3.333.88 C12 Alkene 1.49 1.30 0.00 0.09 Naphthalene 0.10 0.12 3.24 3.73 C12Alkane 3.34 3.21 1.31 1.66 C13 Alkane 3.20 2.90 2.97 3.40 C13 Alkene1.46 1.20 1.17 1.53 2-methylnaphthalene 0.86 0.63 0.64 0.85 C14 Alkene1.07 0.84 0.84 1.04 C14 Alkane 3.34 3.04 3.05 3.24 Acenaphthene 0.310.28 0.28 0.28 C15 Alkene 1.16 0.87 0.87 0.96 C15 Alkane 3.41 3.00 3.022.84 C16 Alkene 0.85 0.58 0.58 0.56 C16 Alkane 3.25 2.67 2.68 2.12 C17Alkene 0.70 0.46 0.46 0.35 C17 Alkane 3.04 2.43 2.44 1.50 C18 Alkene0.51 0.33 0.33 0.19 C18 Alkane 2.71 2.11 2.13 0.99 C19 Alkane 2.39 1.820.38 0.15 C19 Alkene 0.60 0.38 1.83 0.61 C20 Alkene 0.42 0.18 0.26 0.00C20 Alkane 2.05 1.55 1.55 0.37 C21 Alkene 0.31 0.00 0.00 0.00 C21 Alkane1.72 1.45 1.30 0.23 C22 Alkene 0.00 0.00 0.00 0.00 C22 Alkane 1.43 1.111.12 0.00 C23 Alkene 0.00 0.00 0.00 0.00 C23 Alkane 1.09 0.87 0.88 0.00C24 Alkene 0.00 0.00 0.00 0.00 C24 Alkane 0.82 0.72 0.72 0.00 C25 Alkene0.00 0.00 0.00 0.00 C25 Alkane 0.61 0.58 0.56 0.00 C26 Alkene 0.00 0.000.00 0.00 C26 Alkane 0.44 0.47 0.44 0.00 C27 Alkane 0.31 0.37 0.32 0.00C28 Alkane 0.22 0.29 0.23 0.00 C29 Alkane 0.16 0.22 0.15 0.00 C30 Alkane0.00 0.16 0.00 0.00 C31 Alkane 0.00 0.00 0.00 0.00 C32 Alkane 0.00 0.000.00 0.00 Unidentified 13.73 18.59 15.44 15.91 Percent C8+ 74.86 67.5067.50 66.69 Percent C15+ 28.17 22.63 22.25 10.87 Percent Aromatics 5.918.02 11.35 10.86 Percent Paraffins 59.72 54.85 54.19 51.59 Percent C4 toC7 11.41 13.72 16.86 17.40

r-Pyoil Examples 5-10

Six r-pyoil compositions were prepared by distillation of r-pyoilsamples. They were prepared by processing the material according theprocedures described below.

Example 5. r-Pyoil with at Least 90% Boiling by 350° C., 50% BoilingBetween 95° C. and 200° C., and at Least 10% Boiling by 60° C.

A 250 g sample of r-pyoil from Example 3 was distilled through a 30-trayglass Oldershaw column fitted with glycol chilled condensers,thermowells containing thermometers, and a magnet operated refluxcontroller regulated by electronic timer. Batch distillation wasconducted at atmospheric pressure with a reflux rate of 1:1. Liquidfractions were collected every 20 mL, and the overhead temperature andmass recorded to construct the boiling curve presented in FIG. 17. Thedistillation was repeated until approximately 635 g of material wascollected.

Example 6. r-Pyoil with at Least 90% Boiling by 150° C., 50% BoilingBetween 80° C. and 145° C., and at Least 10% Boiling by 60° C.

A 150 g sample of r-pyoil from Example 3 was distilled through a 30-trayglass Oldershaw column fitted with glycol chilled condensers,thermowells containing thermometers, and a magnet operated refluxcontroller regulated by electronic timer. Batch distillation wasconducted at atmospheric pressure with a reflux rate of 1:1. Liquidfractions were collected every 20 mL, and the overhead temperature andmass recorded to construct the boiling curve presented in FIG. 18. Thedistillation was repeated until approximately 200 g of material wascollected.

Example 7. r-Pyoil with at Least 90% Boiling by 350° C., at Least 10% by150° C., and 50% Boiling Between 220° C. and 280° C.

A procedure similar to Example 8 was followed with fractions collectedfrom 120° C. to 210° C. at atmospheric pressure and the remainingfractions (up to 300° C., corrected to atmospheric pressure) under 75torr vacuum to give a composition of 200 g with a boiling point curvedescribed by FIG. 19.

Example 8. r-Pyoil with 90% Boiling Between 250-300° C.

Approximately 200 g of residuals from Example 6 were distilled through a20-tray glass Oldershaw column fitted with glycol chilled condensers,thermowells containing thermometers, and a magnet operated refluxcontroller regulated by electronic timer. One neck of the base pot wasfitted with a rubber septum, and a low flow N₂ purge was bubbled intothe base mixture by means of an 18″ long, 20-gauge steel thermometer.Batch distillation was conducted at 70 torr vacuum with a reflux rate of1:2. Temperature measurement, pressure measurement, and timer controlwere provided by a Camille Laboratory Data Collection System. Liquidfractions were collected every 20 mL, and the overhead temperature andmass recorded. Overhead temperatures were corrected to atmosphericboiling point by means of the Clausius-Clapeyron Equation to constructthe boiling curve presented in FIG. 20 below. Approximately 150 g ofoverhead material was collected.

Example 9. r-Pyoil with 50% Boiling Between 60-80° C.

A procedure similar to Example 5 was followed with fractions collectedboiling between 60° C. and 230° C. to give a composition of 200 g with aboiling point curve described by FIG. 21.

Example 10. r-Pyoil with High Aromatic Content

A 250 g sample of r-pyoil with high aromatic content was distilledthrough a 30-tray glass Oldershaw column fitted with glycol chilledcondensers, thermowells containing thermometers, and a magnet operatedreflux controller regulated by electronic timer. Batch distillation wasconducted at atmospheric pressure with a reflux rate of 1:1. Liquidfractions were collected every 10-20 mL, and the overhead temperatureand mass recorded to construct the boiling curve presented in FIG. 22.The distillation ceased after approximately 200 g of material werecollected. The material contains 34 weight percent aromatic content bygas chromatography analysis.

Table 2 shows the composition of Examples 5-10 by gas chromatographyanalysis.

TABLE 2 Gas Chromatography Analysis of r-Pyoil Examples 5-10. r-PyoilExamples Components 5 6 7 8 9 10 Propene 0.00 0.00 0.00 0.00 0.00 0.00Propane 0.00 0.10 0.00 0.00 0.00 0.00 1,3-r-Butadiene 0.27 1.69 0.000.00 0.00 0.18 Pentene 0.44 1.43 0.00 0.00 0.00 0.48 Pentane 3.95 4.000.00 0.00 0.37 4.59 Unknown 1 0.09 0.28 0.00 0.00 0.00 0.071,3-cyclopentadiene 0.00 0.13 0.00 0.00 0.00 0.00 2-methyl-Pentene 2.753.00 0.00 0.00 5.79 4.98 2-methyl-Pentane 2.63 6.71 0.00 0.00 9.92 5.56Hexane 0.75 4.77 0.00 0.00 11.13 3.71 2-methyl-1,3-cyclopentadiene 0.000.20 0.00 0.00 0.96 0.30 1-methyl-1,3-cyclopentadiene 0.00 0.00 0.000.00 0.00 0.00 2,4 dimethylpentene 0.00 0.35 0.00 0.00 2.06 0.26 Benzene0.00 0.24 0.00 0.00 1.11 0.26 5-methyl-1,3-cyclopentadiene 0.00 0.090.00 0.00 0.15 0.15 Heptene 0.52 5.50 0.00 0.00 6.22 2.97 Heptane 0.137.35 0.17 0.00 10.16 6.85 Toluene 1.18 2.79 0.69 0.00 2.39 6.984-methylheptane 2.54 2.46 3.29 0.00 1.16 3.92 Octene 3.09 4.72 2.50 0.000.48 2.62 Octane 5.77 6.27 3.49 0.00 0.65 4.50 2,4-dimethylheptene 3.922.30 0.61 0.00 0.96 2.58 2,4-dimethylheptane 9.47 5.80 1.30 0.00 3.740.00 Ethylbenzene 0.00 0.00 1.32 0.00 2.43 7.81 m,p-xylene 7.48 4.360.23 0.00 1.09 15.18 Styrene 0.90 1.80 0.40 0.00 2.32 1.47 o-xylene 0.280.00 0.12 0.00 0.00 0.00 Nonane 3.74 5.94 0.41 0.00 6.15 2.55 Nonene1.45 3.87 0.84 0.00 2.53 1.14 MW140 2.36 1.94 1.63 0.00 3.69 2.35 Cumene1.30 1.23 0.54 0.00 2.13 2.43 Decene/methylstyrene 1.54 1.60 1.55 0.000.30 0.48 Decane 4.31 1.68 4.34 0.00 0.48 1.08 Unknown 2 0.96 0.15 0.970.00 0.00 0.24 Indene 0.25 0.00 0.21 0.00 0.00 0.00 Indane 0.33 0.000.33 0.00 0.00 0.08 C11 Alkene 1.83 0.22 1.83 0.00 0.00 0.19 C11 Alkane4.54 0.18 4.75 0.00 0.00 0.39 C12 Alkene 1.68 0.08 2.34 0.00 0.18 0.08Naphthalene 0.09 0.00 0.11 0.00 0.00 0.00 C12 Alkane 4.28 0.09 6.14 0.000.84 0.16 C13 Alkane 4.11 0.00 6.80 3.32 0.68 0.08 C13 Alkene 1.67 0.002.85 0.38 0.37 0.00 2-methylnaphthalene 0.70 0.00 0.00 0.93 0.14 0.00C14 Alkene 0.08 0.00 1.81 3.52 0.00 0.00 C14 Alkane 0.14 0.09 6.20 14.120.00 0.00 Acenaphthylene 0.00 0.00 0.75 0.00 0.00 0.00 C15 Alkene 0.000.00 2.70 3.55 0.00 0.00 C15 Alkane 0.00 0.09 9.40 14.16 0.00 0.07 C16Alkene 0.00 0.00 1.61 2.20 0.00 0.00 C16 Alkane 0.00 0.10 5.44 12.400.00 0.00 C17 Alkene 0.00 0.00 0.10 3.35 0.00 0.00 C17 Alkane 0.00 0.100.26 16.81 0.00 0.00 C18 Alkene 0.00 0.00 0.00 0.67 0.00 0.00 C18 Alkane0.00 0.10 0.00 3.31 0.00 0.00 C19 Alkane 0.00 0.00 0.00 0.13 0.00 0.00C19 Alkene 0.00 0.00 0.00 0.00 0.00 0.00 C20 Alkene 0.00 0.00 0.00 0.000.00 0.00 C20 Alkane 0.00 0.00 0.00 0.00 0.00 0.00 C21 Alkene 0.00 0.000.00 0.00 0.00 0.00 Unidentified 18.51 16.18 21.95 21.13 19.45 13.24Percent C4-C7 12.71 38.55 0.85 0.00 50.25 37.35 Percent C8+ 68.78 45.1777.20 78.87 30.30 49.41 Percent C15+ 0.00 0.38 19.52 56.60 0.00 0.07Percent Aromatics 14.04 12.02 6.27 0.93 11.90 34.70 Percent Paraffins52.35 59.75 55.64 64.26 56.08 44.89

Examples 11-58 Involving Steam Cracking r-Pyoil in a Lab Unit

The invention is further illustrated by the following steam crackingexamples. Examples were performed in a laboratory unit to simulate theresults obtained in a commercial steam cracker. A drawing of the labsteam cracker is shown in FIG. 11. Lab Steam Cracker 910 consisted of asection of ⅜ inch Incoloy™ tubing 912 that was heated in a 24-inchApplied Test Systems three zone furnace 920. Each zone (Zone 1 922 a,Zone 2 922 b, and Zone 3 922 c) in the furnace was heated by a 7-inchsection of electrical coils. Thermocouples 924 a, 924 b, and 924 c werefastened to the external walls at the mid-point of each zone fortemperature control of the reactor. Internal reactor thermocouples 926 aand 926 b were also placed at the exit of Zone 1 and the exit of Zone 2,respectively. The r-pyoil source 930 was fed through line 980 to Iscosyringe pump 990 and fed to the reactor through line 981 a. The watersource 940 was fed through line 982 to ICSO syringe pump 992 and fed topreheater 942 through line 983 a for conversion to steam prior toentering the reactor in line 981 a with pyoil. A propane cylinder 950was attached by line 984 to mass flow controller 994. The plant nitrogensource 970 was attached by line 988 to mass flow controller 996. Thepropane or nitrogen stream was fed through line 983 a to preheater 942to facilitate even steam generation prior to entering the reactor inline 981 a. Quartz glass wool was placed in the 1 inch space between thethree zones of the furnace to reduce temperature gradients between them.In an optional configuration, the top internal thermocouple 922 a wasremoved for a few examples to feed r-pyoil either at the mid-point ofZone 1 or at the transition between Zone 1 and Zone 2 through a sectionof ⅛ inch diameter tubing. The dashed lines in FIG. 11 show the optionalconfigurations. A heavier dashed line extends the feed point to thetransition between Zone 1 and Zone 2. Steam was also optionally added atthese positions in the reactor by feeding water from Isco syringe pump992 through the dashed line 983 b. r-Pyoil, and optionally steam, werethen fed through dashed line 981 b to the reactor. Thus, the reactor canbe operated be feeding various combinations of components and at variouslocations. Typical operating conditions were heating the first zone to600° C., the second zone to about 700° C., and the third zone to 375° C.while maintaining 3 psig at the reactor exit. Typical flow rates ofhydrocarbon feed and steam resulted in a 0.5 sec residence time in one7-inch section of the furnace. The first 7-inch section of the furnace922 a was operated as the convection zone and the second 7-inch section922 b as the radiant zone of a steam cracker. The gaseous effluent ofthe reactor exited the reactor through line 972. The stream was cooledwith shell and tube condenser 934 and any condensed liquids werecollected in glycol cooled sight glass 936. The liquid material wasremoved periodically through line 978 for weighing and gaschromatography analysis. The gas stream was fed through line 976 a forventing through a back-pressure regulator that maintained about 3 psigon the unit. The flow rate was measured with a Sensidyne GilianGilibrator-2 Calibrator. Periodically a portion of the gas stream wassent in line 976 b to a gas chromatography sampling system for analysis.The unit could be was operated in a decoking mode by physicallydisconnecting propane line 984 and attaching air cylinder 960 with line986 and flexible tubing line 974 a to mass flow controlled 994.

Analysis of reaction feed components and products was done by gaschromatography. All percentages are by weight unless specifiedotherwise. Liquid samples were analyzed on an Agilent 7890A using aRestek RTX-1 column (30 meters×320 micron ID, 0.5 micron film thickness)over a temperature range of 35° C. to 300° C. and a flame ionizationdetector. Gas samples were analyzed on an Agilent 8890 gaschromatograph. This GC was configured to analyze refinery gas up to C₆with H₂S content. The system used four valves, three detectors, 2 packedcolumns, 3 micro-packed columns, and 2 capillary columns. The columnsused were the following: 2 ft x 1/16 in, 1 mm i.d. HayeSep A 80/100 meshUltiMetal Plus 41 mm; 1.7 m× 1/16 in, 1 mm i.d. HayeSep A 80/100 meshUltiMetal Plus 41 mm; 2 m x 1/16 in, 1 mm i.d. MolSieve 13X 80/100 meshUltiMetal Plus 41 mm; 3 ft x ⅛ in, 2.1 mm i.d. HayeSep Q 80/100 mesh inUltiMetal Plus; 8 ft x ⅛ in, 2.1 mm i.d. Molecular Sieve 5A 60/80 meshin UltiMetal Plus; 2m×0.32 mm, 5 um thickness DB-1 (123-1015, cut);25m×0.32 mm, 8 um thickness HP-AL/S (19091P-S12). The FID channel wasconfigured to analyze the hydrocarbons with the capillary columns fromC₁ to C₅, while C₆/C₆₊ components are backflushed and measured as onepeak at the beginning of the analysis. The first channel (reference gasHe) was configured to analyze fixed gases (such as CO₂, CO, O2, N2, andH₂S). This channel was run isothermally, with all micro-packed columnsinstalled inside a valve oven. The second TCD channel (third detector,reference gas N2) analyzed hydrogen through regular packed columns. Theanalyses from both chromatographs were combined based on the mass ofeach stream (gas and liquid where present) to provide an overall assayfor the reactor.

A typical run was made as follows:

Nitrogen (130 sccm) was purged through the reactor system, and thereactor was heated (zone1, zone 2, zone 3 setpoints 300° C., 450° C.,300° C., respectively). Preheaters and cooler for post-reactor liquidcollection were powered on. After 15 minutes and the preheater was above100° C., 0.1 mL/min water was added to the preheater to generate steam.The reactor temperature setpoints were raised to 450° C., 600° C., and350° C. for zones 1, 2, and 3, respectively. After another 10 minutes,the reactor temperature setpoints were raised to 600° C., 700° C., and375° C. for zones 1, 2, and 3, respectively. The N₂ was decreased tozero as the propane flow was increased to 130 sccm. After 100 min atthese conditions either r-pyoil or r-pyoil in naphtha was introduced,and the propane flow was reduced. The propane flow was 104 sccm, and ther-pyoil feed rate was 0.051 g/hr for a run with 80% propane and 20%r-pyoil. This material was steam cracked for 4.5 hr (with gas and liquidsampling). Then, 130 sccm propane flow was reestablished. After 1 hr,the reactor was cooled and purged with nitrogen.Steam Cracking with r-Pyoil Example 1.

Table 3 contains examples of runs made in the lab steam cracker withpropane, r-pyoil from Example 1, and various weight ratios of the two.Steam was fed to the reactor in a 0.4 steam to hydrocarbon ratio in allruns. Nitrogen (5% by weight relative to the hydrocarbon) was fed withsteam in the run with only r-pyoil to aid in even steam generation.Comparative Example 1 is an example involving cracking only propane.

TABLE 3 Steam Cracking Examples using r-pyoil from Example 1.Comparative Examples Example 1 11 12 13 14 15 Zone 2 Control Temp 700700 700 700 700 700    Propane (wt %) 100 85 80 67 50 0   r-Pyoil (wt %)0 15 20 33 50 100*    Feed Wt, g/hr 15.36 15.43 15.35 15.4 15.33 15.35 Steam/Hydrocarbon Ratio 0.4 0.4 0.4 0.4 0.4 0.4  Total Accountability, %103.7 94.9 94.5 89.8 87.7 86    Total Products Weight Percent C6+ 1.152.61 2.62 4.38 7.78 26.14  methane 18.04 18.40 17.68 17.51 17.52 12.30 ethane 2.19 2.59 2.46 2.55 2.88 2.44 ethylene 30.69 32.25 31.80 32.3632.97 23.09  propane 24.04 19.11 20.25 16.87 11.66 0.33 propylene 17.8217.40 17.63 16.80 15.36 7.34 i-butane 0.00 0.04 0.04 0.03 0.03 0.01n-butane 0.03 0.02 0.02 0.02 0.02 0.02 propydiene 0.07 0.14 0.13 0.150.17 0.14 acetylene 0.24 0.40 0.40 0.45 0.48 0.41 t-2-butene 0.00 0.190.00 0.00 0.00 0.11 1-butene 0.16 0.85 0.19 0.19 0.20 0.23 i-butylene0.92 0.34 0.87 0.81 0.66 0.81 c-2-butene 0.12 0.15 0.40 0.56 0.73 0.11i-pentane 0.13 0.00 0.00 0.00 0.00 0.00 n-pentane 0.00 0.01 0.01 0.020.02 0.02 1,3-butadiene 1.73 2.26 2.31 2.63 3.02 2.88 methyl acetylene0.20 0.26 0.26 0.30 0.32 0.28 t-2-pentene 0.11 0.08 0.12 0.12 0.12 0.052-methyl-2-butene 0.02 0.01 0.03 0.03 0.02 0.02 1-pentene 0.05 0.09 0.010.02 0.02 0.03 c-2-pentene 0.06 0.01 0.03 0.03 0.03 0.01 pentadiene 10.00 0.01 0.02 0.02 0.02 0.08 pentadiene 2 0.01 0.04 0.04 0.05 0.06 0.16pentadiene 3 0.12 0.21 0.23 0.27 0.30 0.26 1,3-Cyclopentadiene 0.48 0.850.81 1.01 1.25 1.58 pentadiene 4 0.00 0.08 0.08 0.09 0.10 0.07pentadiene 5 0.06 0.17 0.17 0.20 0.23 0.31 CO2 0.00 0.00 0.00 0.00 0.000.00 CO 0.12 0.11 0.05 0.00 0.12 0.74 hydrogen 1.40 1.31 1.27 1.21 1.130.67 Unidentified 0.00 0.00 0.10 1.33 2.79 19.37  Olefin/Aromatics Ratio45.42 21.07 20.91 12.62 7.11 1.42 Total Aromatics 1.15 2.61 2.62 4.387.78 26.14  Propylene + Ethylene 48.51 49.66 49.43 49.16 48.34 30.43 Ethylene/Propylene Ratio 1.72 1.85 1.80 1.93 2.15 3.14 *5% N2 was alsoadded to facilitate steam generation. Analysis has been normalized toexclude it.

As the amount of r-pyoil used is increased relative to propane, therewas an increase in the formation of dienes. For example, bothr-butadiene and cyclopentadiene increased as more r-pyoil is added tothe feed. Additionally, aromatics (C6+) increased considerably withincreased r-pyoil in the feed.

Accountability decreased with increasing amounts of r-pyoil in theseexamples. It was determined that some r-pyoil in the feed was being heldup in the preheater section. Due to the short run times, accountabilitywas negatively affected. A slight increase in the slope of the reactorinlet line corrected the issue (see Example 24). Nonetheless, even withan accountability of 86% in Example 15, the trend was clear. The overallyield of r-ethylene and r-propylene decreased from about 50% to lessthan about 35% as the amount of r-pyoil in the feed increased. Indeed,feeding r-pyoil alone produced about 40% of aromatics (C6+) andunidentified higher boilers (see Example 15 and Example 24).

r-Ethylene Yield—r-Ethylene yield showed an increase from 30.7% to >32%as 15% r-pyoil was co-cracked with propane. The yield of r-ethylene thenremained about 32% until >50% r-pyoil was used. With 100% r-pyoil, theyield of r-ethylene decreased to 21.5% due to the large amount ofaromatics and unidentified high boilers (>40%). Since r-pyoil cracksfaster than propane, a feed with an increased amount of r-pyoil willcrack faster to more r-propylene. The r-propylene can then react to formr-ethylene, diene and aromatics. When the concentration of r-pyoil wasincreased the amount of r-propylene cracked products was also increased.Thus, the increased amount of dienes can react with other dienes andolefins (like r-ethylene) leading to even more aromatics formation. So,at 100% r-pyoil in the feed, the amount of r-ethylene and r-propylenerecovered was lower due to the high concentration of aromatics thatformed. In fact, the olefin/aromatic dropped from 45.4 to 1.4 as r-pyoilwas increased to 100% in the feed. Thus, the yield of r-ethyleneincreased as more r-pyoil was added to the feed mixture, at least toabout 50% r-pyoil. Feeding pyoil in propane provides a way to increasethe ethylene/propylene ratio on a steam cracker.

r-Propylene Yield—r-Propylene yield decreased with more r-pyoil in thefeed. It dropped from 17.8% with propane only to 17.4% with 15% r-pyoiland then to 6.8% as 100% r-pyoil was cracked. r-Propylene formation didnot decrease in these cases. r-Pyoil cracks at lower temperature thanpropane. As r-propylene is formed earlier in the reactor it has moretime to converted to other materials—like dienes and aromatics andr-ethylene. Thus, feeding r-pyoil with propane to a cracker provides away to increase the yield of ethylene, dienes and aromatics.

The r-ethylene/r-propylene ratio increased as more r-pyoil was added tothe feed because an increase concentration of r-pyoil made r-propylenefaster, and the r-propylene reacted to other cracked products—likedienes, aromatics and r-ethylene.

The ethylene to propylene ratio increased from 1.72 to 3.14 going from100% propane to 100% r-pyoil cracking. The ratio was lower for 15%r-pyoil (0.54) than 20% r-pyoil (0.55) due to experimental error withthe small change in r-pyoil feed and the error from having just one runat each condition.

The olefin/aromatic ratio decreased from 45 with no r-pyoil in the feedto 1.4 with no propane in the feed. The decrease occurred mainly becauser-pyoil cracked more readily than propane and thus more r-propylene wasproduced faster. This gave the r-propylene more time to react further—tomake more r-ethylene, dienes, and aromatics. Thus, aromatics increased,and r-propylene decreased with the olefin/aromatic ratio decreasing as aresult.

r-Butadiene increased as the concentration of r-pyoil in the feedincreased, thus providing a way to increase r-butadiene yield.r-Butadiene increased from 1.73% with propane cracking, to about 2.3%with 15-20% r-pyoil in the feed, to 2.63% with 33% r-pyoil, and to 3.02%with 50% r-pyoil. The amount was 2.88% at 100% r-pyoil. Example 24showed 3.37% r-butadiene observed in another run with 100% r-pyoil. Thisamount may be a more accurate value based on the accountability problemsthat occurred in Example 15. The increase in r-butadiene was the resultof more severity in cracking as products like r-propylene continued tocrack to other materials.

Cyclopentadiene increased with increasing r-pyoil except for thedecrease in going from 15%-20% r-pyoil (from 0.85 to 0.81). Again, someexperimental error was likely. Thus, cyclopentadiene increased from0.48% cracking propane only, to about 0.85% at 15-20% r-pyoil in thereactor feed, to 1.01% with 33% r-pyoil, to 1.25 with 50% r-pyoil, and1.58% with 100% r-pyoil. The increase in cyclobutadiene was also theresult of more severity in cracking as products like r-propylenecontinued to crack to other materials. Thus, cracking r-pyoil withpropane provided a way to increase cyclopentadiene production.

Operating with r-pyoil in the feed to the steam cracker resulted in lesspropane in the reactor effluent. In commercial operation, this wouldresult in a decreased mass flow in the recycle loop. The lower flowwould decrease cryogenic energy costs and potentially increase capacityon the plant if it is capacity constrained. Additionally, lower propanein the recycle loop would debottleneck the r-propylene fractionator ifit is already capacity limited.

Steam Cracking with r-Pyoil Examples 1-4.

Table 4 contains examples of runs made with the r-pyoil samples found inTable1 with a propane/r-pyoil weight ratio of 80/20 and 0.4 steam tohydrocarbon ratio.

TABLE 4 Examples using r-PyOil Examples 1-4 under similar conditions.Examples 16 17 18 19 r-Pyoil from Table 1 1 2 3 4 Zone 2 Control Temp700 700 700 700 Propane (wt %) 80 80 80 80 r-Pyoil (wt %) 20 20 20 20 N2(wt %) 0 0 0 0 Feed Wt, g/hr 15.35 15.35 15.35 15.35 Steam/HydrocarbonRatio 0.4 0.4 0.4 0.4 Total Accountability, % 94.5 96.4 95.6 95.3 TotalProducts Weight Percent C6+ 2.62 2.86 3.11 2.85 methane 17.68 17.3617.97 17.20 ethane 2.46 2.55 2.67 2.47 ethylene 31.80 30.83 31.58 30.64propane 20.25 21.54 19.34 21.34 propylene 17.63 17.32 17.18 17.37i-butane 0.04 0.04 0.04 0.04 n-butane 0.02 0.01 0.02 0.03 propadiene0.13 0.06 0.09 0.12 acetylene 0.40 0.11 0.26 0.37 t-2-butene 0.00 0.000.00 0.00 1-butene 0.19 0.19 0.20 0.19 i-butylene 0.87 0.91 0.91 0.98c-2-butene 0.40 0.44 0.45 0.52 i-pentane 0.00 0.14 0.16 0.16 n-pentane0.01 0.03 0.03 0.03 1,3-butadiene 2.31 2.28 2.33 2.27 methyl acetylene0.26 0.23 0.23 0.24 t-2-pentene 0.12 0.13 0.14 0.13 2-methyl-2-butene0.03 0.04 0.04 0.03 1-pentene 0.01 0.02 0.02 0.02 c-2-pentene 0.03 0.060.05 0.04 pentadiene 1 0.02 0.00 0.00 0.00 pentadiene 2 0.04 0.02 0.020.01 pentadiene 3 0.23 0.17 0.00 0.25 1,3-Cyclopentadiene 0.81 0.72 0.760.71 pentadiene 4 0.08 0.00 0.00 0.00 pentadiene 5 0.17 0.08 0.09 0.08CO2 0.00 0.00 0.00 0.00 CO 0.05 0.00 0.00 0.00 hydrogen 1.27 1.22 1.261.21 Unidentified 0.10 0.65 1.04 0.69 Olefin/Aromatics Ratio 20.91 18.6617.30 18.75 Total Aromatics 2.62 2.86 3.11 2.85 Propylene + Ethylene49.43 48.14 48.77 48.01 Ethylene/Propylene Ratio 1.80 1.78 1.84 1.76

Steam cracking of the different r-pyoil Examples 1-4 at the sameconditions gave similar results. Even the lab distilled sample ofr-pyoil (Example 19) cracked like the other samples. The highestr-ethylene and r-propylene yield was for Example 16, but the range was48.01-49.43. The r-ethylene/r-propylene ratio varied from 1.76 to 1.84.The amount of aromatics (C6+) only varied from 2.62 to 3.11. Example 16also produced the smallest yield of aromatics. The r-pyoil used for thisexample (r-Pyoil Example 1, Table 1) contained the largest amount ofparaffins and the lowest amount of aromatics. Both are desirable forcracking to r-ethylene and r-propylene.

Steam Cracking with r-Pyoil Example 2.

Table 5 contains runs made in the lab steam cracker with propane(Comparative Example 2), r-pyoil Example 2, and four runs with apropane/pyrolysis oil weight ratio of 80/20. Comparative Example 2 andExample 20 were run with a 0.2 steam to hydrocarbon ratio. Steam was fedto the reactor in a 0.4 steam to hydrocarbon ratio in all otherexamples. Nitrogen (5% by weight relative to the r-pyoil) was fed withsteam in the run with only r-pyoil (Example 24).

TABLE 5 Examples using r-Pyoil Example 2. Comparative Examples Example 220 21 22 23 24 Zone 2 Control Temp 700° C. 700° C. 700° C. 700° C. 700°C. 700° C. Propane (wt %) 100 80 80 80 80 0   r-Pyoil (wt %) 0 20 20 2020 100*    Feed Wt, g/hr 15.36 15.35 15.35 15.35 15.35 15.35 Steam/Hydrocarbon Ratio 0.2 0.2 0.4 0.4 0.4 0.4  Total Accountability, %100.3 93.8 99.1 93.4 96.4 97.9  Total Products Weight Percent C6+ 1.362.97 2.53 2.98 2.86 22.54  methane 18.59 19.59 17.34 16.64 17.36 11.41 ethane 2.56 3.09 2.26 2.35 2.55 3.00 ethylene 30.70 32.51 31.19 29.8930.83 24.88  propane 23.00 17.28 21.63 23.84 21.54 0.38 propylene 18.0616.78 17.72 17.24 17.32 10.94  i-butane 0.04 0.03 0.03 0.05 0.04 0.02n-butane 0.01 0.03 0.03 0.03 0.01 0.09 propadiene 0.05 0.10 0.12 0.120.06 0.12 acetylene 0.12 0.35 0.40 0.36 0.11 0.31 t-2-butene 0.00 0.000.00 0.00 0.00 0.00 1-butene 0.17 0.20 0.18 0.18 0.19 0.25 i-butylene0.87 0.80 0.91 0.94 0.91 1.22 c-2-butene 0.14 0.40 0.40 0.44 0.44 1.47i-pentane 0.14 0.13 0.00 0.00 0.14 0.13 n-pentane 0.00 0.01 0.02 0.030.03 0.01 1,3-butadiene 1.74 2.35 2.20 2.18 2.28 3.37 methyl acetylene0.18 0.22 0.26 0.24 0.23 0.23 t-2-pentene 0.13 0.14 0.12 0.12 0.13 0.142-methyl-2-butene 0.03 0.04 0.03 0.04 0.04 0.10 1-pentene 0.01 0.03 0.010.01 0.02 0.05 c-2-pentene 0.04 0.04 0.03 0.04 0.06 0.18 pentadiene 10.00 0.01 0.01 0.02 0.00 0.14 pentadiene 2 0.01 0.02 0.03 0.02 0.02 0.19pentadiene 3 0.00 0.24 0.19 0.24 0.17 0.50 1,3-Cyclopentadiene 0.52 0.830.65 0.71 0.72 1.44 pentadiene 4 0.00 0.00 0.00 0.00 0.00 0.01pentadiene 5 0.06 0.09 0.08 0.08 0.08 0.15 CO2 0.00 0.00 0.00 0.00 0.000.00 CO 0.07 0.00 0.00 0.00 0.00 0.19 hydrogen 1.36 1.28 1.28 1.21 1.220.63 Unidentified 0.00 0.00 0.34 0.00 0.65 15.89  Olefin/Aromatics Ratio38.54 18.39 21.26 17.55 18.66 2.00 Total Aromatics 1.36 2.97 2.53 2.982.86 22.54  Propylene +-Ethylene 48.76 49.29 48.91 47.13 48.14 35.82 Ethylene/Propylene Ratio 1.70 1.94 1.76 1.73 1.78 2.27 *5% N2 was alsoadded to facilitate steam generation. Analysis has been normalized toexclude it.

Comparing Example 20 to Examples 21-23 shows that the increased feedflow rate (from 192 sccm in Example 20 to 255 sccm with more steam inExamples 21-23) resulted in less conversion of propane and r-pyoil dueto the 25% shorter residence time in the reactor (r-ethylene andr-propylene: 49.3% for Example 20 vs 47.1, 48.1, 48.9% for Examples21-23). r-Ethylene was higher in Example 21 with the increased residencetime since propane and r-pyoil cracked to higher conversion ofr-ethylene and r-propylene and some of the r-propylene can then beconverted to additional r-ethylene. And conversely, r-propylene washigher in the higher flow examples with a higher steam to hydrocarbonratio (Example 21-23) since it has less time to continue reacting. Thus,Examples 21-23 produced a smaller amount of other components:r-ethylene, C6+(aromatics), r-butadiene, cyclopentadiene, etc., thanfound in Example 20.

Examples 21-23 were run at the same conditions and showed that there wassome variability in operation of the lab unit, but it was sufficientlysmall that trends can be seen when different conditions are used.

Example 24, like example 15, showed that the r-propylene and r-ethyleneyield decreased when 100% r-pyoil was cracked compared to feed with 20%r-pyoil. The amount decreased from about 48% (in Examples 21-23) to 36%.Total aromatics was greater than 20% of the product as in Example 15.

Steam Cracking with r-Pyoil Example 3.

Table 6 contains runs made in the lab steam cracker with propane andr-pyoil Example 3 at different steam to hydrocarbon ratios.

TABLE 6 Examples using r-Pyoil Example 3. Examples 25 26 Zone 2 ControlTemp 700° C. 700° C. Propane (wt %) 80 80 r-Pyoil (wt %) 20 20 N2 (wt %)0 0 Feed Wt, g/hr 15.33 15.33 Steam/Hydrocarbon Ratio 0.4 0.2 TotalAccountability, % 95.6 92.1 Total Products Weight Percent C6+ 3.11 3.42methane 17.97 18.57 ethane 2.67 3.01 ethylene 31.58 31.97 propane 19.3417.43 propylene 17.18 17.17 i-butane 0.04 0.04 n-butane 0.02 0.03propadiene 0.09 0.10 acetylene 0.26 0.35 t-2-butene 0.00 0.00 1-butene0.20 0.20 i-butylene 0.91 0.88 c-2-butene 0.45 0.45 i-pentane 0.16 0.17n-pentane 0.03 0.02 1,3-butadiene 2.33 2.35 methyl acetylene 0.23 0.22t-2-pentene 0.14 0.15 2-methyl-2-butene 0.04 0.04 1-pentene 0.02 0.02c-2-pentene 0.05 0.04 pentadiene 1 0.00 0.00 pentadiene 2 0.02 0.02pentadiene 3 0.00 0.25 1,3-Cyclopentadiene 0.76 0.84 pentadiene 4 0.000.00 pentadiene 5 0.09 0.10 CO2 0.00 0.00 CO 0.00 0.00 hydrogen 1.261.24 Unidentified 1.04 0.92 Olefin/Aromatics Ratio 17.30 15.98 TotalAromatics 3.11 3.42 Propylene + Ethylene 48.77 49.14 Ethylene/PropyleneRatio 1.84 1.86

The same trends observed from cracking with r-pyoil Examples 1-2 weredemonstrated for cracking with propane and r-pyoil Example 3. Example 25compared to Example 26 showed that a decrease in the feed flow rate (to192 sccm in Example 26 with less steam from 255 sccm in Example 25)resulted in greater conversion of the propane and r-pyoil due to the 25%greater residence time in the reactor (r-ethylene and r-propylene:48.77% for Example 22 vs 49.14% for the lower flow in Example 26).r-Ethylene was higher in Example 26 with the increased residence timesince propane and r-pyoil cracked to higher conversion of r-ethylene andr-propylene and some of the r-propylene was then converted to additionalr-ethylene. Thus, Example 25, with the shorter residence time produced asmaller amount of other components: r-ethylene, C6+(aromatics),r-butadiene, cyclopentadiene, etc., than found in Example 26.

Steam Cracking with r-Pyoil Example 4.

Table 7 contains runs made in the lab steam cracker with propane andpyrolysis oil sample 4 at two different steam to hydrocarbon ratios.

TABLE 7 Examples using Pyrolysis Oil Example 4. Examples 27 28 Zone 2Control Temp 700° C. 700° C. Propane (wt %) 80 80 r-Pyoil (wt %) 20 20N2 (wt %) 0 0 Feed Wt, g/hr 15.35 15.35 Steam/Hydrocarbon Ratio 0.4 0.6Total Accountability, % 95.3 95.4 Total Products Weight Percent C6+ 2.852.48 methane 17.20 15.37 ethane 2.47 2.09 ethylene 30.64 28.80 propane21.34 25.58 propylene 17.37 17.79 i-butane 0.04 0.05 n-butane 0.03 0.03propadiene 0.12 0.12 acetylene 0.37 0.35 t-2-butene 0.00 0.00 1-butene0.19 0.19 i-butylene 0.98 1.03 c-2-butene 0.52 0.53 i-pentane 0.16 0.15n-pentane 0.03 0.05 1,3-butadiene 2.27 2.15 methyl acetylene 0.24 0.25t-2-pentene 0.13 0.12 2-methyl-2-butene 0.03 0.04 1-pentene 0.02 0.02c-2-pentene 0.04 0.05 pentadiene 1 0.00 0.00 pentadiene 2 0.01 0.02pentadiene 3 0.25 0.27 1,3-Cyclopentadiene 0.71 0.65 pentadiene 4 0.000.00 pentadiene 5 0.08 0.08 CO2 0.00 0.00 CO 0.00 0.00 hydrogen 1.211.15 Unidentified 0.69 0.63 Olefin/Aromatics Ratio 18.75 20.94 TotalAromatics 2.85 2.48 Propylene + Ethylene 48.01 46.59 Ethylene/PropyleneRatio 1.76 1.62

The results in Table 7 showed the same trends as discussed with Example20 vs Examples 21-23 in Table 5 and Example 25 vs Example 26 in Table 6.At a smaller steam to hydrocarbon ratio, higher amounts of r-ethyleneand r-propylene and higher amounts of aromatics were obtained at theincreased residence time. The r-ethylene/r-propylene ratio was alsogreater.

Thus, comparing Example 20 with Examples 21-23 in Table 5, Example 25with Example 26, and Example 27 with Example 28 showed the same effect.Decreasing the steam to hydrocarbon ratio decreased the total flow inthe reactor. This increased the residence time. As a result, there wasan increase in the amount of r-ethylene and r-propylene produced. Ther-ethylene to r-propylene ratio was larger which indicated that somer-propylene reacted to other products like r-ethylene. There was also anincrease in aromatics(C6+) and dienes.

Examples of Cracking r-Pyoils from Table 2 with Propane

Table 8 contains the results of runs made in the lab steam cracker withpropane (Comparative example 3) and the six r-pyoil samples listed inTable 2. Steam was fed to the reactor in a 0.4 steam to hydrocarbonratio in all runs.

Examples 30, 33, and 34 were the results of runs with r-pyoil havinggreater than 35% C4-C7. The r-pyoil used in Example 40 contained 34.7%aromatics. Comparative Example 3 was a run with propane only. Examples29, 31, and 32 were the results of runs with r-pyoil containing lessthan 35% C4-C7.

TABLE 8 Examples of steam cracking with propane and r-pyoils.Comparative Examples Example 3 29 30 31 32 33 34 r-Pyoil Feed from Table2 5 6 7 8 9 10 Zone 2 Control Temp, ° C. 700 700 700 700 700 700 700Propane (wt %) 100 80 80 80 80 80 80 r-Pyoil (wt %) 0 20 20 20 20 20 20Feed Wt, g/hr 15.36 15.32 15.33 15.33 15.35 15.35 15.35Steam/Hydrocarbon Ratio 0.4 0.4 0.4 0.4 0.4 0.4 0.4 TotalAccountability, % 103 100 100.3 96.7 96.3 95.7 97.3 Total ProductsWeight Percent C6+ 1.13 2.86 2.64 3.03 2.34 3.16 3.00 methane 17.6917.17 15.97 17.04 16.42 18.00 16.41 ethane 2.27 2.28 2.12 2.26 2.59 2.632.19 ethylene 29.85 31.03 29.23 30.81 30.73 30.80 28.99 propane 24.9021.86 25.13 21.70 23.79 20.99 24.57 propylene 18.11 17.36 17.78 17.2318.08 17.90 17.32 i-butane 0.05 0.04 0.05 0.04 0.05 0.04 0.05 n-butane0.02 0.02 0.04 0.02 0.00 0.00 0.02 propadiene 0.08 0.14 0.12 0.14 0.040.04 0.10 acetylene 0.31 0.42 0.36 0.42 0.04 0.06 0.31 t-2-butene 0.000.00 0.00 0.00 0.00 0.00 0.00 1-butene 0.16 0.18 0.19 0.18 0.19 0.200.18 i-butylene 0.91 0.93 1.00 0.92 0.93 0.90 0.95 c-2-butene 0.13 0.510.50 0.50 0.34 0.68 0.61 i-pentane 0.14 0.00 0.15 0.00 0.16 0.16 0.15n-pentane 0.00 0.04 0.05 0.04 0.00 0.00 0.06 1,3-butadiene 1.64 2.282.15 2.26 2.48 2.23 2.04 methyl acetylene 0.19 0.28 0.24 0.28 n/a 0.240.24 t-2-pentene 0.12 0.12 0.12 0.12 0.13 0.13 0.11 2-methyl-2-butene0.03 0.03 0.03 0.03 0.04 0.03 0.03 1-pentene 0.11 0.02 0.02 0.02 0.010.02 0.02 c-2-pentene 0.01 0.03 0.04 0.03 0.11 0.10 0.05 pentadiene 10.00 0.02 0.00 0.02 0.00 0.00 0.00 pentadiene 2 0.01 0.03 0.03 0.04 0.010.05 0.02 pentadiene 3 0.14 0.25 0.00 0.25 0.00 0.00 0.001,3-Cyclopentadiene 0.44 0.77 0.69 0.77 0.22 0.30 0.63 pentadiene 4 0.000.00 0.00 0.00 0.00 0.00 0.00 pentadiene 5 0.06 0.08 0.08 0.08 0.09 0.080.07 CO2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 CO 0.11 0.00 0.07 0.00 0.000.00 0.11 hydrogen 1.36 1.26 1.21 1.25 1.18 1.25 1.22 unidentified 0.000.00 0.00 0.52 0.00 0.00 0.56 Olefin/Aromatics Ratio 45.81 18.79 19.6617.64 22.84 16.91 17.06 Total Aromatics 1.13 2.86 2.64 3.03 2.34 3.163.00 Propylene + Ethylene 47.96 48.39 47.01 48.04 48.82 48.70 46.31Ethylene/Propylene Ratio 1.65 1.79 1.64 1.79 1.70 1.72 1.67

The examples in Table 8 involved using an 80/20 mix of propane with thevarious distilled r-pyoils. The results were like those in previousexamples involving cracking r-pyoil with propane. All the examplesproduced an increase in aromatics and dienes relative to crackingpropane only. As a result, the olefins to aromatic ratio was lower forcracking the combined feeds. The amount of r-propylene and r-ethyleneproduced was 47.01-48.82% for all examples except for the 46.31%obtained with the r-pyoil with 34.7% aromatic content (using r-pyoilExample 10 in Example 34). Except for that difference, the r-pyoilsperformed similarly, and any of them can be fed with C-2 to C-4 in asteam cracker. r-Pyoils having high aromatic content like r-pyoilExample 10 may not be the preferred feed for a steam cracker, and ar-pyoil having less than about 20% aromatic content should be considereda more preferred feed for co-cracking with ethane or propane.

Example of Steam Cracking r-Pyoils from Table 2 with Natural Gasoline.

Table 9 contains the results of runs made in the lab steam cracker witha natural gasoline sample from a supplier and the r-pyoils listed inTable 2. The natural gasoline material was greater than 99% C5-C8 andcontained greater than 70% identified paraffins and about 6% aromatics.The material had an initial boiling point of 100° F., a 50% boilingpoint of 128° F., a 95% boiling point of 208° F., and a final boilingpoint of 240° F. No component greater than C9 were identified in thenatural gasoline sample. It was used as a typical naphtha stream for theexamples.

The results presented in Table 9 include examples involving cracking thenatural gasoline (Comparative example 4), or cracking a mixture ofnatural gasoline and the r-pyoil samples listed in Table 2. Steam wasfed to the reactor in a 0.4 steam to hydrocarbon ratio in all runs.Nitrogen (5% by weight relative to the hydrocarbon) was fed with waterto facilitate even steam generation. Examples 35, 37, and 38 involvedruns with r-pyoils containing very little C15+. Example 38 illustratedthe results of a run with greater than 50% C15+ in the r-pyoil.

The gas flow of the reactor effluent and the gas chromatography analysisof the stream were used to determine the weight of gas product, and thenthe weight of other liquid material needed for 100% accountability wascalculated. This liquid material was typically 50-75% aromatics, andmore typically 60-70%. An actual assay of the liquid sample wasdifficult for these examples. The liquid product in most of theseexamples was an emulsion that was hard to separate and assay. Since thegas analysis was reliable, this method allowed an accurate comparison ofthe gaseous products while still having an estimate of the liquidproduct if it was completely recovered.

TABLE 9 Results of Cracking r-Pyoil with Natural Gasoline. ComparativeExamples Example 4 35 36 37 38 39 40 r-Pyoil Feed from Table 2 NaturalGasoline 5   6   7   8   9   10    Zone 2 Control Temp 700    700   700    700    700    700    700    Natural Gasoline (wt %) 100    80   80    80    80    80    80    r-Pyoil (wt %) 0   20    20    20    20   20    20    N2 (wt %) 5*   5*   5*   5*   5*   5*   5*   Feed Wt, g/hr15.4  15.3  15.4  15.4  15.4  15.4  15.4  Gas Exit Flow, sccm 221.2  206.7   204.5   211.8   211.3   202.6   207.8   Gas WeightAccountability, % 92.5  83.1  81.5  79.9  83.9  81.7  84.3  TotalProducts Weight Percent C6+ 9.54 7.86 6.32 8.05 7.23 7.15 5.75 methane19.19  18.33  16.98  17.80  19.46  17.88  15.67  ethane 3.91 3.91 3.243.86 4.02 3.52 2.77 ethylene 27.34  26.14  28.24  24.96  27.74  26.42 29.39  propane 0.42 0.40 0.38 0.36 0.37 0.37 0.42 propylene 12.97 12.49  13.61  10.87  11.80  12.34  16.10  i-butane 0.03 0.03 0.03 0.020.02 0.02 0.03 n-butane 0.11 0.07 0.00 0.05 0.00 0.05 0.00 propadiene0.22 0.18 0.10 0.18 0.08 0.22 0.11 acetylene 0.40 0.34 0.11 0.33 0.090.41 0.13 t-2-butene 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1-butene 0.440.39 0.40 0.32 0.38 0.39 0.46 i-butylene 0.91 0.89 0.91 0.65 0.76 0.861.30 c-2-butene 2.98 2.85 2.98 2.28 2.58 2.94 3.58 i-pentane 0.08 0.030.02 0.05 0.04 0.03 0.02 n-pentane 5.55 1.95 0.84 2.21 1.72 1.45 1.331,3-butadiene 3.17 3.09 3.77 2.94 3.54 3.48 3.78 methyl acetylene 0.370.32 0.40 0.31 0.36 0.39 n/a t-2-pentene 0.14 0.12 0.12 0.12 0.14 0.120.12 2-methyl-2-butene 0.07 0.06 0.04 0.07 0.08 0.07 0.06 1-pentene 0.100.08 0.08 0.09 0.11 0.10 0.09 c-2-pentene 0.20 0.17 0.07 0.19 0.12 0.090.08 pentadiene 1 0.35 0.12 0.02 0.19 0.13 0.09 0.06 pentadiene 2 0.800.52 0.16 0.59 0.54 0.40 0.29 pentadiene 3 0.48 0.10 0.00 0.46 0.00 0.000.00 1,3-Cyclopentadiene 1.03 1.00 0.56 0.98 0.56 1.09 0.56 pentadiene 40.00 0.00 0.00 0.00 0.00 0.00 0.00 pentadiene 5 0.11 0.11 0.13 0.10 0.130.12 0.00 CO2 0.01 0.00 0.00 0.00 0.00 0.00 0.00 CO 0.00 0.00 0.10 0.000.00 0.06 0.13 hydrogen 1.00 0.92 0.94 0.87 0.95 0.93 1.03 Other HighBoilers- 8.09 17.54  19.45  21.12  17.06  19.01  16.75  calculated** C6+and Other Calculated 17.63  25.40  25.77  29.17  24.28  26.17  22.50 High Boilers Ethylene and Propylene 40.31  38.63  41.86  35.83  39.54 38.76  45.48  Ethylene/Propylene Ratio 2.11 2.09 2.07 2.30 2.35 2.141.83 Olefin/Aromatics in gas 5.38 6.15 8.10 5.59 6.74 6.81 9.74 effluent*5% Nitrogen was also added to facilitate steam generation. Analysis hasbeen normalized to exclude it. **Calculated theoretical amount neededfor 100% accountability based on the actual reactor effluent gas flowrate and gas chromatography analysis.

The cracking examples in Table 9 involved using an 80/20 mix of naturalgasoline with the various distilled r-pyoils. The natural gasoline andr-pyoils examples produced an increase in C6+(aromatics), unidentifiedhigh boilers, and dienes relative to cracking propane only or r-pyoiland propane (see Table 8). The increase in aromatics in the gas phasewas about double compared to cracking 20% by weight r-pyoil withpropane. Since the liquid product was typically greater than 60%aromatics, the total amount of aromatics was probably 5 times greaterthan cracking 20% by weight r-pyoil with propane. The amount ofr-propylene and r-ethylene produced was generally lower by about 10%.The r-ethylene and r-propylene yield ranged from 35.83-41.86% for allexamples except for the 45.48% obtained with high aromatic r-pyoil(using Example 10 material in Example 40). This is almost in the rangeof the yields obtained from cracking r-pyoil and propane (46.3-48.8% inTable 7). Example 40 produced the highest amount of r-propylene (16.1%)and the highest amount of r-ethylene (29.39%). This material alsoproduced the lowest r-ethylene/r-propylene ratio which suggests thatthere was less conversion of r-propylene to other products than in theother examples. This result was unanticipated. The high concentration ofaromatics (34.7%) in the r-pyoil feed appeared to inhibit furtherreaction of r-propylene. It is thought that r-pyoils having an aromaticcontent of 25-50% will see similar results. Co-cracking this materialwith natural gasoline also produced the lowest amount of C6+ andunidentified high boilers, but this stream produced the mostr-butadiene. The natural gasoline and r-pyoil both cracked easier thanpropane so the r-propylene that formed reacted to give the increase inr-ethylene, aromatics, dienes, and others. Thus, ther-ethylene/r-propylene ratio was above 2 in all these examples, exceptin Example 40. The ratio in this example (1.83) was similar to the1.65-1.79 range observed in Table 8 for cracking r-pyoil and propane.Except for these differences, the r-pyoils performed similarly and anyof them can be fed with naphtha in a steam cracker.

Steam Cracking r-Pyoil with Ethane

Table 10 shows the results of cracking ethane and propane alone, andcracking with r-pyoil Example 2. The examples from cracking eitherethane or ethane and r-pyoil were operated at three Zone 2 controltemperatures: 700° C., 705° C., and 710° C.

TABLE 10 Examples of Cracking Ethane and r-pyoil at differenttemperatures. Comparative Comparative Comparative ComparativeComparative Examples Example 5 41 Example 6 42 Example 7 43 Example 3Example 8 Zone 2 Control Temp 700° C. 700° C. 705° C. 705° C. 710° C.710° C. 700° C. 700° C. Propane or Ethane in Feed Ethane Ethane EthaneEthane Ethane Ethane Propane Propane Propane or Ethane (wt %) 100 80 10080 100 80 100 80 r-Pyoil (wt %) 0 20 0 20 0 20 0 20 Feed Wt, g/hr 10.4810.47 10.48 10.47 10.48 10.47 15.36 15.35 Steam/Hydrocarbon Ratio 0.40.4 0.4 0.4 0.4 0.4 0.4 0.4 Total Accountability, % 107.4 94.9 110.4597.0 104.4 96.8 103.0 96.4 Total Products Weight Percent C6+ 0.22 1.420.43 2.18 0.64 2.79 1.13 2.86 methane 1.90 6.41 2.67 8.04 3.69 8.8017.69 17.36 ethane 46.36 39.94 38.75 33.77 32.15 26.82 2.27 2.55ethylene 44.89 44.89 51.27 48.53 55.63 53.41 29.85 30.83 propane 0.080.18 0.09 0.18 0.10 0.16 24.90 21.54 propylene 0.66 2.18 0.84 1.99 1.031.86 18.11 17.32 i-butane 0.00 0.00 0.00 0.00 0.00 0.00 0.05 0.04n-butane 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.01 propadiene 0.41 0.260.37 0.22 0.31 0.19 0.08 0.06 acetylene 0.00 0.01 0.00 0.01 0.00 0.010.31 0.11 t-2-butene 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1-butene0.04 0.07 0.05 0.07 0.06 0.07 0.16 0.19 i-butylene 0.00 0.15 0.00 0.150.00 0.14 0.91 0.91 c-2-butene 0.12 0.19 0.13 0.11 0.13 0.08 0.13 0.44i-pentane 0.59 0.05 0.04 0.06 0.05 0.06 0.14 0.14 n-pentane 0.01 0.010.00 0.00 0.00 0.00 0.00 0.03 1,3-butadiene 0.96 1.45 1.34 1.69 1.722.06 1.64 2.28 methyl acetylene n/a n/a n/a n/a n/a n/a 0.19 0.23t-2-pentene 0.03 0.04 0.02 0.04 0.03 0.05 0.12 0.13 2-methyl-2-butene0.02 0.00 0.03 0.00 0.03 0.00 0.03 0.04 1-pentene 0.00 0.00 0.00 0.000.00 0.00 0.11 0.02 c-2-pentene 0.03 0.04 0.03 0.04 0.03 0.03 0.01 0.06pentadiene 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 pentadiene 2 0.000.00 0.00 0.00 0.00 0.00 0.01 0.02 pentadiene 3 0.00 0.00 0.00 0.00 0.000.00 0.14 0.17 1,3-Cyclopentadiene 0.03 0.06 0.02 0.05 0.02 0.05 0.440.72 pentadiene 4 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 pentadiene 50.00 0.03 0.00 0.03 0.00 0.03 0.06 0.08 CO2 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 CO 0.00 0.00 0.00 0.00 0.00 0.00 0.11 0.00 hydrogen 3.462.66 3.94 2.90 4.36 3.43 1.36 1.22 unidentified 0.00 0.00 0.00 0.00 0.000.00 0.00 0.65 Olefin/Aromatics 216.63 34.87 126.61 24.25 91.78 20.8045.81 18.66 Total Aromatics 0.22 1.42 0.43 2.18 0.64 2.79 1.13 2.86Propylene + Ethylene 45.56 47.07 52.11 50.52 56.65 55.28 47.96 48.14Ethylene/Propylene Ratio 67.53 20.59 60.95 24.44 54.13 28.66 1.65 1.78

A limited number of runs with ethane were made. As can be seen in theComparative Examples 5-7 and Comparative Example 3, conversion of ethaneto products occurred more slowly than with propane. Comparative Example5 with ethane and Comparative Example 3 with propane were run at thesame molar flow rates and temperatures. However, conversion of ethanewas only 52% (100%-46% ethane in product) vs 75% for propane. However,the r-ethylene/r-propylene ratio was much higher (67.53 vs 1.65) asethane cracking produced mainly r-ethylene. The olefin to aromaticsratio for ethane cracking was also much higher for ethane cracking. TheComparative Examples 5-7 and Examples 41-43 compare cracking ethane toan 80/20 mixture of ethane and r-pyoil at 700° C., 705° C. and 710° C.Production of total r-ethylene plus r-propylene increased with bothethane feed and the combined feed when the temperature was increased (anincrease from about 46% to about 55% for both). Although the r-ethyleneto r-propylene ratio decreased for ethane cracking with increasingtemperature (from 67.53 at 700° C. to 60.95 at 705° C. to 54.13 at 710°C.), the ratio increased for the mixed feed (from 20.59 to 24.44 to28.66). r-Propylene was produced from the r-pyoil and some continued tocrack generating more cracked products such as r-ethylene, dienes andaromatics. The amount of aromatics in propane cracking with r-pyoil at700° C. (2.86% in Comparative Example 8) was about the same as crackingethane and r-pyoil at 710° C. (2.79% in Example 43).

Co-cracking ethane and r-pyoil required higher temperature to obtainmore conversion to products compared to co-cracking with propane andr-pyoil. Ethane cracking produced mainly r-ethylene. Since a hightemperature was required to crack ethane, cracking a mixture of ethaneand r-pyoil produced more aromatics and dienes as some r-propylenereacted further. Operation in this mode would be appropriate ifaromatics and dienes were desired with minimal production ofr-propylene.

Examples of Cracking r-Pyoil and Propane 5° C. Higher or Lower thanCracking Propane.

Table 11 contains runs made in the lab steam cracker with propane at695° C., 700° C., and 705° C. (Comparative examples 3, 9-10) andExamples 44-46 using 80/20 propane/r-pyoil weight ratios at thesetemperatures. Steam was fed to the reactor in a 0.4 steam to hydrocarbonratio in all runs. r-Pyoil Example 2 was cracked with propane in theseexamples.

TABLE 11 Examples using r-Pyoil Example 2 at 700° C. +/− 5° C.Comparative Comparative Comparative Examples Example 9 Example 3 Example10 44 45 46 Zone 2 Control Temp, ° C. 695 700 705 695 700 705 Propane(wt %) 100 100 100 80 80 80 r-Pyoil Example 2 (wt %) 0 0 0 20 20 20 Zone2 Exit Temp, ° C. 683 689 695 685 691 696 Feed Wt, g/hr 15.36 15.3615.36 15.35 15.35 15.35 Steam/Hydrocarbon Ratio 0.4 0.4 0.4 0.4 0.4 0.4Total Accountability, % 105 103 100.2 99.9 96.4 94.5 Total ProductsWeight Percent C6+ 0.76 1.13 1.58 2.44 2.86 4.02 methane 15.06 17.6920.02 14.80 17.36 19.33 ethane 1.92 2.27 2.49 2.20 2.55 2.63 ethylene25.76 29.85 33.22 27.14 30.83 33.06 propane 33.15 24.90 18.96 28.2121.54 15.38 propylene 18.35 18.11 16.61 17.91 17.32 15.43 i-butane 0.050.05 0.03 0.06 0.04 0.03 n-butane 0.02 0.02 0.02 0.03 0.01 0.02propadiene 0.07 0.08 0.10 0.10 0.06 0.12 acetylene 0.22 0.31 0.42 0.270.11 0.47 t-2-butene 0.00 0.00 0.00 0.00 0.00 0.00 1-butene 0.15 0.160.16 0.19 0.19 0.17 i-butylene 0.95 0.91 0.80 1.01 0.91 0.72 c-2-butene0.11 0.13 0.13 0.49 0.44 0.33 i-pentane 0.12 0.14 0.13 0.15 0.14 0.12n-pentane 0.00 0.00 0.00 0.02 0.03 0.02 1,3-butadiene 1.22 1.64 2.001.93 2.28 2.39 methyl acetylene 0.14 0.19 0.23 0.20 0.23 0.26t-2-pentene 0.11 0.12 0.12 0.12 0.13 0.12 2-methyl-2-butene 0.02 0.030.02 0.04 0.04 0.03 1-pentene 0.11 0.11 0.05 0.02 0.02 0.01 c-2-pentene0.01 0.01 0.06 0.04 0.06 0.03 pentadiene 1 0.00 0.00 0.00 0.01 0.00 0.00pentadiene 2 0.00 0.01 0.01 0.01 0.02 0.01 pentadiene 3 0.12 0.14 0.160.24 0.17 0.22 1,3-Cyclopentadiene 0.30 0.44 0.59 0.59 0.72 0.83pentadiene 4 0.00 0.00 0.00 0.00 0.00 0.00 pentadiene 5 0.05 0.06 0.060.07 0.08 0.08 CO2 0.00 0.00 0.00 0.00 0.00 0.00 CO 0.00 0.11 0.47 0.000.00 0.00 hydrogen 1.21 1.36 1.50 1.09 1.22 1.32 unidentified 0.00 0.000.00 0.61 0.65 2.84 Olefin/Aromatics Ratio 62.38 45.81 34.23 20.43 18.6613.33 Total Aromatics 0.76 1.13 1.58 2.44 2.86 4.02 Propylene + Ethylene44.12 47.96 49.83 45.05 48.14 48.49 Ethylene/Propylene Ratio 1.40 1.652.00 1.52 1.78 2.14Operating at a higher temperature in the propane tube gave a higherconversion of propane—mainly to r-ethylene and r-propylene (increasingfrom 44.12% to 47.96% to 49.83% in Comparative Example 9, 3, and 10respectively). The higher the temperature the more r-ethylene wasproduced at the expense of r-propylene (r-ethylene/r-propylene ratioincreased from 1.40 to 1.65 to 2.0 in Comparative Examples 9, 3, and10). Aromatics also increased with higher temperature. The same trendswere observed with cracking the mixed streams in Examples 44-46:increased r-ethylene and r-propylene from 45.05% to 48.49%), increasedr-ethylene/r-propylene ratio (from 1.52 to 2.14), and an increase intotal aromatics (from 2.44% to 4.02%). It is known that r-pyoilconversion to cracked products is greater at a given temperaturerelative to propane.

For the condition where the mixed feed has a 5° C. lower reactor outlettemperature consider the following two cases:

-   -   Case A. Comparative Example 3 (Propane at 700° C.) and Example        441 (80/20 at 695° C.)    -   Case B. Comparative Example 103 (Propane at 705° C.) and Example        452 (80/20 at 700° C.)

Operating the combined tube at 5° C. lower temperature allowed isolationof more r-propylene relative to the higher temperature. For example,operating at 700° C. in Example 45 vs 705° C. in Example 46, r-propylenewas 17.32% vs 15.43%. Similarly, operating at 695° C. in Example 44 vs700° C. in Example 45, r-propylene was 17.91% vs 17.32%. r-Propylene andr-ethylene yield increased as temperature was increased, but thisoccurred at the expense of r-propylene as shown by the increasingr-ethylene to r-propylene ratio (from 1.52 at 695° C. in Example 44 to2.14 at 705° C. in Example 46). The ratio also increased for propanefeed, but it started from a slightly lower level. Here, the ratioincreased from 1.40 at 695° C. to 2.0 at 705° C.

The lower temperature in the combined tube still gave almost as goodconversion to r-ethylene and r-propylene (For Case A: 47.96% for propanecracking vs 45.05% for combined cracking and for Case B: 49.83% forpropane cracking vs 48.15% combined). Operation of the combined tube atlower temperature also decreased aromatics and dienes. Thus, this modeis preferred if more r-propylene is desired relative to r-ethylene whileminimizing production of C6+(aromatics) and dienes.

For the condition where the mixed tube has a 5° C. higher reactor outlettemperature, consider the following two cases:

-   -   Case A. Comparative Example 3 (Propane at 700° C. and Example 46        (80/20 at 705° C.)    -   Case B. Comparative Example 9 (Propane at 695° C.) and Example        45 (80/20 at 700° C.)

Running lower temperature in the propane tube decreased the conversionof propane and decreased the r-ethylene to r-propylene ratio. The ratiowas lower at lower temperatures for both the combined feed and thepropane feed cases. The r-pyoil conversion to cracked products wasgreater at a given temperature relative to propane. It was seen thatoperating 5° C. higher in the combined tube caused production of morer-ethylene and less r-propylene relative to the lower temperature. Thismode—with the higher temperature in the combined tube—gave an increasedconversion to r-ethylene plus r-propylene (For Case A: 47.96% forpropane cracking in Comparative Example 3 vs 48.49% in Example 46 forcombined cracking, and for Case B: 44.11% for propane cracking(Comparative Example 9) vs 48.15% for combined cracking (Example 45) at5° C. higher temperature).

Operation in this mode (5° C. higher temperature in the combined tube)increases production of r-ethylene, aromatics, and dienes, if sodesired. By operating the propane tube at a lower temperature—whichoperates at a lower ethylene to propylene ratio—the r-propyleneproduction can be maintained compared to running both tubes at the sametemperature. For example, operating the combined tube at 700° C. and thepropane tube at 695° C. resulted in 18.35% and 17.32%, respectively, ofr-propylene. Running both at 695° C. would give 0.6% more r-propylene inthe combined tube. Thus, this mode is preferred if more aromatics,dienes, and slightly more r-ethylene is desired while minimizingproduction loss of r-propylene.

The temperatures were measured at the exit of Zone 2 which is operatedto simulate the radiant zone of the cracking furnace. These temperaturesare shown in Table 11. Although there were considerable heat loses inoperating a small lab unit, the temperatures showed that the exittemperatures for the combined feed cases were 1-2° C. higher than forthe corresponding propane only feed case. Steam cracking is anendothermic process. There is less heat needed in cracking with pyoiland propane than when cracking propane alone, and thus the temperaturedoes not decrease as much.

Examples Feeding r-Pyoil or r-Pyoil and Steam at Various Locations.

Table 12 contains runs made in the lab steam cracker with propane andr-pyoil Example 3. Steam was fed to the reactor in a 0.4 steam tohydrocarbon ratio in all runs. r-Pyoil and steam were fed at differentlocations (see configurations in FIG. 11). In Example 48, the reactorinlet temperature was controlled at 380° C., and r-pyoil was fed as agas. The reactor inlet temperature was usually controlled at 130-150° C.when r-pyoil was fed as a liquid (Example 49) in the typical reactorconfiguration.

TABLE 12 Examples with r-Pyoil and Steam Fed at Different Locations.Examples* 47 48 49 50 51 52 Zone 2 Control Temp 700° C. 700° C. 700° C.700° C. 700° C. 700° C. Propane (wt %) 80 80 80 80 80 80 r-Pyoil (wt %)20 20 20 20 20 20 Feed Wt, g/hr 15.33 15.33 15.33 15.33 15.33 15.33Steam/hydrocarbon ratio 0.4 0.4 0.4 0.4 0.4 0.4 Total Accountability, %95.8 97.1 97.83 97.33 96.5 97.3 Total Products Weight Percent C6+ 3.033.66 4.50 3.32 3.03 3.38 methane 17.37 18.49 19.33 17.46 19.85 17.38ethane 2.58 3.04 3.27 2.60 3.18 2.35 ethylene 30.30 31.07 31.53 30.9332.10 30.75 propane 21.90 19.10 16.57 20.11 17.79 21.96 propylene 16.8216.78 15.97 17.24 16.64 16.14 i-butane 0.04 0.04 0.03 0.04 0.03 0.04n-butane 0.04 0.03 0.03 0.03 0.03 0.03 propadiene 0.10 0.09 0.09 0.110.11 0.12 acetylene 0.35 0.33 0.33 0.36 0.34 0.40 t-2-butene 0.00 0.000.00 0.00 0.00 0.00 1-butene 0.19 0.19 0.19 0.19 0.18 0.18 i-butylene0.94 0.79 0.72 0.86 0.73 0.86 c-2-butene 0.43 0.39 0.39 0.43 0.37 0.39i-pentane 0.16 0.16 0.16 0.16 0.15 0.15 n-pentane 0.04 0.02 0.02 0.030.02 0.04 1,3-butadiene 2.15 2.16 2.22 2.28 2.20 2.29 methyl acetylene0.21 0.21 0.20 0.23 0.22 0.24 t-2-pentene 0.13 0.13 0.13 0.13 0.12 0.122-methyl-2-butene 0.04 0.03 0.03 0.03 0.03 0.03 1-pentene 0.02 0.01 0.020.02 0.02 0.02 c-2-pentene 0.05 0.03 0.03 0.03 0.03 0.04 pentadiene 10.00 0.00 0.01 0.00 0.00 0.00 pentadiene 2 0.03 0.02 0.02 0.02 0.01 0.01pentadiene 3 0.25 0.07 0.22 0.24 0.22 0.24 1,3-Cyclopentadiene 0.72 0.760.83 0.80 0.79 0.81 pentadiene 4 0.00 0.00 0.00 0.00 0.00 0.00pentadiene 5 0.08 0.08 0.08 0.08 0.08 0.08 CO2 0.00 0.00 0.00 0.00 0.050.00 CO 0.00 0.00 0.00 0.00 0.23 0.00 hydrogen 1.24 1.23 1.23 1.21 1.421.25 Unidentified 0.79 1.09 1.80 1.06 0.00 0.71 Olefin/Aromatics Ratio17.27 14.36 11.67 16.08 17.71 15.43 Total Aromatics 3.03 3.66 4.50 3.323.03 3.38 Propylene + Ethylene 47.12 47.85 47.50 48.17 48.75 46.89Ethylene/Propylene Ratio 1.80 1.85 1.97 1.79 1.93 1.91 *Example 47-r-Pyoil fed between zone 1 and zone 2: Proxy For Crossover *Example 48-r-Pyoil and steam fed between zone 1 and zone 2: Proxy for Crossover*Example 49- r-Pyoil and steam fed at midpoint of zone 1: Proxy forDownstream of Inlet *Example 50- r-Pyoil fed at midpoint of zone 1:Proxy for Downstream of Inlet *Example 51- r-Pyoil fed as gas at inletof zone 1 *Example 49- r-Pyoil fed as liquid at inlet of zone 1

Feeding propane and r-pyoil as a gas at reactor inlet (Example 51) gavea higher conversion to r-ethylene and r-propylene compared to Example 52where the r-pyoil was fed as a liquid. Some conversion was due toheating the stream to near 400° C. where some cracking occurred. Sincethe r-pyoil was vaporized outside the reactor, no heat supplied for thatpurpose was required by the furnace. Thus, more heat was available forcracking. As a result, a greater amount of r-ethylene and r-propylene(48.75%) was obtained compared to that obtained when the r-pyoil was fedas a liquid at the top of the reactor (46.89% in Example 52).Additionally, r-pyoil entering the reactor as a gas decreased residencetime in the reactor which resulted in lower total aromatics and anincreased olefin/aromatics ratio for Example 51.

In the other examples (47-50) either r-pyoil or r-pyoil and steam wasfed at the simulated crossover between the convection zone and theradiant zone of a steam cracking furnace (between Zone 1 and Zone 2 ofthe lab furnace) or at the mid-point of Zone 1. There was littledifference in the cracking results except for the aromatic content inExample 49. Feeding r-pyoil and steam at the midpoint of Zone 1 resultedin the greatest amount of aromatics. The number of aromatics was alsohigh when steam was cofed with r-pyoil between Zone 1 and Zone 2(Example 48). Both examples had a longer overall residence time forpropane to react before the streams were combined compared to the otherExamples in the table. Thus, the particular combination of longerresidence time for cracking propane and a slightly shorter residencetime for r-pyoil cracking in Example 49 resulted in a greater amount ofaromatics as cracked products.

Feeding r-pyoil as a liquid at the top of reactor (Example 52) gave thelowest conversion of all the conditions. This was due to the r-pyoilrequiring vaporization which needed heat. The lower temperature in Zone1 resulted in less cracking when compared to Example 51.

Higher conversion to r-ethylene and r-propylene was obtained by feedingthe r-pyoil at the crossover or the midpoint of the convection sectionfor one main reason. The propane residence time in the top of thebed—before introduction of r-pyoil or r-pyoil and steam—was lower. Thus,propane can achieve higher conversion to r-ethylene and r-propylenerelative to Example 52 with a 0.5 sec residence time for the entire feedstream. Feeding propane and r-pyoil as a gas at reactor inlet (Example51) gave the highest conversion to r-ethylene and r-propylene becausenone of the furnace heat was used in vaporization of r-pyoil as wasrequired for the other examples.

Decoking Examples from Cracking r-Pyoil Example 5 with Propane orNatural Gasoline.

Propane was cracked at the same temperature and feed rate as an 80/20mixture of propane and r-pyoil from Example 5 and an 80/20 mixture ofnatural gasoline and r-pyoil from Example 5. All examples were operatedin the same way. The examples were run with a Zone 2 control temperatureof 700° C. When the reactor was at stable temperature, propane wascracked for 100 minutes, followed by 4.5 hr of cracking propane, orpropane and r-pyoil, or natural gasoline and r-pyoil, followed byanother 60 min of propane cracking. The steam/hydrocarbon ratio wasvaried in these comparative examples from 0.1 to 0.4. The propanecracking results are shown in Table 13 as Comparative Examples 11-13.The results presented in Table 14 include examples (Examples 53-58)involving cracking an 80/20 mixture of propane or natural gasoline withr-pyoil from Example 5 at different steam to hydrocarbon ratios.Nitrogen (5% by weight relative to the hydrocarbon) was fed with steamin the examples with natural gasoline and r-pyoil to provide even steamgeneration. In the examples involving cracking r-pyoil with naturalgasoline, the liquid samples were not analyzed. Rather, the measuredreactor effluent gas flow rate and gas chromatography analysis were usedto calculate the theoretical weight of unidentified material for 100%accountability.

Following each steam cracking run, decoking of the reactor tube wasperformed. Decoking involved heating all three zones of the furnace to700° C. under 200 sccm N2 flow and 124 sccm steam. Then, 110 sccm airwas introduced to bring the oxygen concentration to 5%. Then, the airflow was slowly increased to 310 sccm as the nitrogen flow was decreasedover two hours. Next, the furnace temperature was increased to 825° C.over two hours. These conditions were maintained for 5 hours. Gaschromatography analysis were performed every 15 minutes beginning withthe introduction of the air stream. The amount of carbon was calculatedbased on the amount of CO2 and CO in each analysis. The amount of carbonwas totalized until no CO was observed, and the amount of CO2 was lessthan 0.05%. The results (mg carbon by gas chromatography analysis) fromdecoking the propane comparative examples are found in Table 13. Theresults from the r-pyoil examples is found in Table 14.

TABLE 13 Comparative Examples of Cracking with Propane. ExamplesComparative Comparative Comparative Example 11 Example 12 Example 13Zone 2 Control Temp, ° C. 700° C. 700° C. 700° C. Propane (wt %) 100 100100 r-Pyoil (wt %) 0 0 0 N2 (wt %) 0 0 0 Feed Wt, g/hr 15.36 15.36 15.36Steam/Hydrocarbon Ratio 0.1 0.2 0.4 Total Accountability, % 98.71 101.3099.96 Total Products Weight Percent C6+ 1.71 1.44 1.10 Methane 20.3419.92 17.98 Ethane 3.04 2.83 2.25 Ethylene 32.48 32.29 30.43 Propane19.04 20.26 24.89 Propylene 17.72 17.88 18.19 i-butane 0.04 0.04 0.04n-butane 0.03 0.00 0.00 Propadiene 0.08 0.04 0.04 Acetylene 0.31 0.030.04 t-2-butene 0.00 0.00 0.00 1-butene 0.18 0.18 0.17 i-butylene 0.780.82 0.93 c-2-butene 0.15 0.14 0.13 i-pentane 0.15 0.15 0.14 n-pentane0.00 0.00 0.00 1,3-butadiene 1.93 1.90 1.68 methyl acetylene 0.18 0.180.19 t-2-pentene 0.14 0.14 0.12 2-methyl-2-butene 0.03 0.03 0.031-pentene 0.01 0.01 0.01 c-2-pentene 0.01 0.11 0.10 pentadiene 1 0.000.00 0.00 pentadiene 2 0.01 0.01 0.01 pentadiene 3 0.00 0.00 0.001,3-Cyclopentadiene 0.17 0.16 0.14 pentadiene 4 0.00 0.00 0.00pentadiene 5 0.07 0.00 0.01 CO2 0.00 0.00 0.00 CO 0.00 0.00 0.00Hydrogen 1.41 1.43 1.39 Unidentified 0.00 0.00 0.00 Olefin/AromaticsRatio 31.53 37.20 47.31 Total Aromatics 1.71 1.44 1.10 Propylene +Ethylene 50.20 50.17 48.62 Ethylene/Propylene Ratio 1.83 1.81 1.67Carbon from Decoking, mg 16 51 1.5

TABLE 14 Examples of Cracking Propane or Natural Gasoline and r-Pyoil.Examples 53 54 55 56 57 58 Propane or Natural Gasoline Propane PropanePropane Nat Gas Nat Gas Nat Gas Zone 2 Control Temp 700 700 700 700   700    700    Propane/Nat Gas (wt %) 80 80 80 80    80    80    r-Pyoil(wt %) 20 20 20 20    20    20    N2 (wt %) 0 0 0 5*   5*   5*   FeedWt, g/hr 15.32 15.32 15.32 15.29  15.29  15.29  Steam/Hydrocarbon Ratio0.1 0.2 0.4 0.4  0.6  0.7  Total Accountability, % 95.4 99.4 97.5100**   100**   100**   Total Products Weight Percent C6+ 2.88 2.13 2.305.69 4.97 5.62 Methane 18.83 16.08 16.62 15.60  16.81  18.43  Ethane3.56 2.85 2.27 2.97 3.43 3.63 Ethylene 30.38 28.17 30.20 27.71  27.74 26.94  Propane 19.81 25.60 24.07 0.40 0.43 0.36 Propylene 18.37 18.8318.13 14.76  14.48  12.04  i-butane 0.04 0.06 0.05 0.03 0.03 0.02n-butane 0.00 0.00 0.00 0.00 0.00 0.00 Propadiene 0.05 0.05 0.04 0.090.09 0.08 Acetylene 0.04 0.04 0.05 0.12 0.10 0.10 t-2-butene 0.00 0.000.00 0.00 0.00 0.00 1-butene 0.23 0.22 0.19 0.45 0.43 0.44 i-butylene0.81 0.97 0.97 1.27 1.02 1.04 c-2-butene 0.63 0.76 0.55 3.38 3.31 2.94i-pentane 0.19 0.18 0.16 0.02 0.02 0.03 n-pentane 0.01 0.01 0.04 1.271.12 2.08 1,3-butadiene 2.11 2.29 2.45 3.64 3.52 3.45 methyl acetylene0.17 n/a n/a 0.41 0.37 0.37 t-2-pentene 0.16 0.13 0.12 0.12 0.12 0.132-methyl-2-butene 0.03 0.03 0.03 0.05 0.06 0.09 1-pentene 0.02 0.02 0.020.08 0.10 0.12 c-2-pentene 0.11 0.10 0.09 0.08 0.09 0.11 pentadiene 10.00 0.00 0.00 0.05 0.08 0.14 pentadiene 2 0.01 0.03 0.02 0.23 0.36 0.53pentadiene 3 0.00 0.00 0.00 0.00 0.00 0.00 1,3-Cyclopentadiene 0.26 0.260.25 0.50 0.55 0.58 pentadiene 4 0.00 0.00 0.00 0.00 0.00 0.00pentadiene 5 0.09 0.08 0.08 0.00 0.00 0.12 CO2 0.00 0.00 0.00 0.02 0.000.00 CO 0.00 0.00 0.00 0.06 0.06 0.03 Hydrogen 1.21 1.12 1.24 0.96 0.950.95 Unidentified 0.00 0.00 0.00 20.04  19.77  19.63  Olefin/AromaticsRatio 18.48 24.43 23.07 9.22 10.46  8.67 Total Aromatics 2.88 2.13 2.305.69 4.97 5.62 Propylene +-Ethylene 48.75 47.00 48.33 42.47  42.22 38.98  Ethylene/Propylene Ratio 1.65 1.50 1.67 1.88 1.92 2.24 Carbonfrom Decoking, mg 96 44 32 90    71    23    *5% N2 was also added tofacilitate steam generation. Analysis has been normalized to exclude it.**100% accountability based on actual reactor effluent gas flow rate andgas chromatography analysis and calculation to give theoretical mass ofunidentified products.

The cracking results showed the same general trends that were seen inthe other cases, such as r-propylene and r-ethylene yield and totalaromatics increasing with a lower steam to hydrocarbon ratio due to thelonger residence time in the reactor. These runs were made to determinethe amount of carbon generated when a r-pyoil was cracked with propaneor natural gasoline. These were short runs but they was sufficientlyaccurate to see trends in coking. Cracking propane produced the leastcoking. The carbon produced ranged from 16 to 51 mg at 0.2 or lesssteam/ghydrocarbon ratio. Coking was the smallest at a 0.4steam/hydrocarbon ratio. In fact, only 1.5 mg of carbon was determinedafter decoking in Comparative 13. A much longer run time is needed toimprove accuracy. Since most commercial plants operate at a steam tohydrocarbon ratio of 0.3 or higher, the 51 mg obtained at 0.2 ratio maynot be unreasonable and may be considered a baseline for other feeds.For the r-pyoil/propane feed in Examples 53-55, increasing the ratiofrom 0.1 to 0.2 to 0.4 decreased the amount of carbon obtained from 96mg (Example 53) to 32 mg (Example 55). Even the 44 mg of carbon at a 0.2ratio (Example 54) was not unreasonable. Thus, using a 0.4 ratio for thecombined r-pyoil and propane feed inhibited coke formation similar tousing a 0.2-0.4 ratio for propane. Cracking r-pyoil with naturalgasoline required a 0.7 ratio (Example 58) to decrease the carbonobtained to the 20-50 mg range. At a 0.6 ratio, (Example 57) 71 mg ofcarbon was still obtained. Thus, operation of an 80/20 mixture ofnatural gasoline and r-pyoil should use a ratio of 0.7 or greater toprovide runtimes typical for operation of propane cracking.

Increasing the steam to hydrocarbon ratio decreased the amount of cokeformed in cracking propane, propane and r-pyoil, and natural gasolineand r-pyoil. A higher ratio was required as a heavier feedstock wascracked. Thus, propane required the lowest ratio to obtain low cokeformation. Cracking propane and r-pyoil required a ratio of about 0.4. Arange of 0.4 to 0.6 would be adequate to allow typical commercialruntimes between decoking. For the natural gasoline and r-pyoil mixture,even a higher ratio was required. In this case, a ratio of 0.7 or aboveis needed. Thus, operating at a steam to hydrocarbon ratio of 0.7 to 0.9would be adequate to allow typical commercial runtimes between decoking.

Example 59—Plant Test

About 13,000 gallons from tank 1012 of r-pyoil were used in the planttest as show in FIG. 12. The furnace coil outlet temperature wascontrolled either by the testing coil (Coil-A 1034 a or Coil-B 1034 b)outlet temperature or by the propane coil (Coil C 1034 c, coil D 1034 dthrough F) outlet temperature, depending on the objective of the test.In FIG. 12 the steam cracking system with r-pyoil 1010; 1012 is ther-pyoil tank; 1020 is the r-pyoil tank pump; 1024 a and 1226 b are TLE(transfer line exchanger); 1030 a, b,c is the furnace convectionsection; 1034 a, b, c, d are the coils in furnace firebox (the radiantsection); 1050 is the r-pyoil transfer line; 1052 a, b are the r-pyoilfeed that is added into the system; 1054 a, b, c, d are the regularhydrocarbon feed; 1058 a, b, c, d—are dilution steam; 1060 a and 1060 bare cracked effluent. The furnace effluent is quenched, cooled toambient temperature and separated out condensed liquid, the gas portionis sampled and analyzed by gas chromatograph.

For the testing coils, propane flow 1054 a and 1054 b were controlledand measured independently. Steam flow 1058 a and 1058 b were eithercontrolled by Steam/HC ratio controller or in an AUTO mode at a constantflow, depending on the objective of the test. In the non-testing coils,the propane flow was controlled in AUTO mode and steam flow wascontrolled in a ratio controller at Steam/Propane=0.3.

r-pyoil was obtained from tank 1012 through r-pyoil flow meters and flowcontrol valves into propane vapor lines, from where r-pyoil flowed alongwith propane into the convection section of the furnace and further downinto the radiant section also called the firebox. FIG. 12 shows theprocess flow.

The r-pyoil properties are shown in and Table 15 and FIG. 23. Ther-pyoil contained a small amount of aromatics, less than 8 wt %, but alot of alkanes (more than 50%), thus making this material as a preferredfeedstock for steam cracking to light olefins. However, the r-pyoil hada wide distillation range, from initial boiling point of about 40° C. toan end point of about 400° C., as shown in Table 15 and FIGS. 24 and 25,covering a wide range of carbon numbers (C₄ to C₃₀ as shown in Table15). Another good characteristic of this r-pyoil is its low sulfurcontent of less than 100 ppm, but the r-pyoil had high nitrogen (327ppm) and chlorine (201 ppm) content. The composition of the r-pyoil bygas chromatography analysis is shown in Table 16.

TABLE 15 Properties of r-pyoil for plant test. Physical PropertiesDensity, 22.1° C., g/ml 0.768 Viscosity, 22.1 C., cP 1.26 InitialBoiling Point, ° C. 45 Flash Point, ° C. Below −1.1 Pour Point, ° C.−5.5 Impurities Nitrogen, ppmw 327 Sulfur, ppmw 74 Chlorine, ppmw 201Hydrocarbons, wt % Total Identified alkanes 58.8 Total IdentifiedAromatics 7.2 Total Identified Olefins 16.7 Total Identified Dienes 1.1Total Identified Hydrocarbons 83.5

TABLE 16 r-Pyoil composition. Component wt % Component wt % Component wt% Component wt % Propane 0.17 2,4-dimethylheptene 1.52 C12-Alkane 3.21C19-Alkane 1.81 1,3-Butadiene 0.97 2,4-dimethylheptane 3.98 C13-Alkene1.19 C20-Alkene 0.25 Pentene 0.40 Ethylbenzene 3.07 C13-Alkane 2.91C20-Alkane 1.53 Pentane 3.13 m,p-xylene 0.66 2-methylnapthalene 0.62C21-Alkene 0.00 2-methyl-Pentene 2.14 Styrene 1.11 C14-Alkene 0.83C21-Alkane 1.28 2-methyl-Pentane 2.46 Mol. Welght = 140 1.73 C14-Alkane3.02 C22-Alkane 1.10 Hexane 1.83 Nonane 2.81 acenapthalene 0.19C23-Alkane 0.87 2,4-dimethytpentene 0.20 Cumene 0.96 C15-alkene 0.86C24-Alkane 0.72 Benzene 0.17 Decene/methylstyrene 1.16 C15-alkane 3.00C25-Alkane 0.57 5-methyl-1,3-cyclopentadiene 0.17 Decane 3.16 C16-Alkene0.58 C26-Alkane 0.47 Heptene 1.15 Indene 0.20 C16-Alkane 2.56 C27-Alkane0.36 Heptane 2.87 Indane 0.26 C17-Alkene 0.46 c28-Alkane 0.28 Toluene1.07 C11-Alkene 1.31 C17-Alkene 2.42 c29-Alkane 0.22 4-methylheptane1.65 C11-Alkane 3.29 C18-Alkene 0.32 C30-Alkane 0.17 Octene 1.51Napthanlene 0.00 C18-Alkane 2.10 Total Identified 83.5% Octane 2.77C12-Alkene 1.29 C19-Alkene 0.37

Before the plant test started, eight (8) furnace conditions (morespecifically speaking, eight conditions on the testing coils) werechosen. These included r-pyoil content, coil outlet temperature, totalhydrocarbon feeding rate, and the ratio of steam to total hydrocarbon.The test plan, objective and furnace control strategy are shown in Table17. “Float Mode” means the testing coil outlet temperature is notcontrolling the furnace fuel supply. The furnace fuel supply iscontrolled by the non-testing coil outlet temperature, or the coils thatdo not contain r-pyoil.

TABLE 17 Plan for the plant test of r-pyoil co-cracking with propane.Pro- Pyoil/ Pyoil/ Stm/ pane/ Con- COT, Pyoil Py/ TOTAL, coil, coil, HCcoil, dition ° F. w % C₃H₈ KLB/HR GPM lb/hr ratio klb/hr Base- 1500 00.000 6.0 0.00 0 0.3 6.00 line 1A Float 5 0.053 6.0 0.79 300 0.3 5.70Mode 1B Float 10 0.111 6.0 1.58 600 0.3 5.40 Mode 1C & Float 15 0.1766.0 2.36 900 0.3 5.10 2A Mode 2B Lower 15 0.176 6.0 2.36 900 0.3 5.10 byat least 10 F. than the base- line 3A & 1500 15 0.176 6.0 2.36 900 0.35.10 2C 3B 1500 15 0.176 6.9 2.72 1035 0.3 5.87 4A 1500 15 0.176 6.02.36 900 0.4 5.10 4B 1500 15 0.176 6.0 2.36 900 0.5 5.10 5A Float 4.80.050 6.3 0.79 300 0.3 6.00 Mode 5B At 2B 4.8 0.050 6.3 0.79 302 0.36.00 COT

The results of r-Pyoil addition can be observed differently depending onhow propane flow, steam/HC ratio and furnace are controlled.Temperatures at crossover and coil outlet changed differently dependingon how propane flow and steam flow are maintained and how the furnace(the fuel supply to the firebox) was controlled. There were six coils inthe testing furnace. There were several ways to control the furnacetemperature via the fuel supply to the firebox. One of them was tocontrol the furnace temperature by an individual coil outlettemperature, which was used in the test. Both a testing coil and anon-testing coil were used to control the furnace temperature fordifferent test conditions.

Example 59.1—at Fixed Propane Flow, Steam/HC Ratio and Furnace FuelSupply (Condition 5A)

In order to check the r-pyoil 1052 a addition effect, propane flow andsteam/HC ratio were held constant, and furnace temperature was set tocontrol by a non-testing coil (Coil-C) outlet temperature. Then r-pyoil1052 a, in liquid form, without preheating, was added into the propaneline at about 5% by weight.

Temperature changes: After the r-pyoil 1052 a addition, the crossovertemperature dropped about 10° F. for A and B coil, COT dropped by about7° F. as shown in Table 18. There are two reasons that the crossover andCOT temperature dropped. One, there was more total flow in the testingcoils due to r-pyoil 1052 a addition, and two, r-pyoil 1052 aevaporation from liquid to vapor in the coils at the convection sectionneeded more heat thus dropping the temperature down. With a lower coilinlet temperature at the radiant section, the COT also dropped. The TLEexit temperature went up due to a higher total mass flow through the TLEon the process side.

Cracked gas composition change: As can be seen from the results in Table18, methane and r-ethylene decreased by about 1.7 and 2.1 percentagepoints, respectively, while r-propylene and propane increased by 0.5 and3.0 percentage points, respectively. The propylene concentrationincreased as did the propylene:ethylene ratio relative to the baselineof no pyoil addition. This was the case even though the propaneconcentration also increased. Others did not change much. The change inr-ethylene and methane was due to the lower propane conversion at thehigher flow rate, which was shown by a much higher propane content inthe cracked gas.

TABLE 18 Changes When Hydrocarbon Mass Flow Increases By Adding r-pyoilTo Propane At 5% At Constant Propane Flow, Steam/HC Ratio And FireboxCondition. Base-line Base-line 5A Add in Pyoil A&B Propane flow, klb/hr11.87 11.86 11.85 A&B Pyoil Flow, lb/hr 0 0 593 A&B Steam flow, lb/hr3562 3556 3737 A&B total HC flow, klb/hr 11.87 11.86 12.44 Pyoil/(poil +propane), % 0.0 0.0 4.8 Steam/HC, ratio 0.30 0.30 0.30 A&B Crossover T,F 1092 1091 1081 A&B COT, F 1499 1499 1492 A&B TLE Exit T, F 691 691 698A&B TLE Inlet, PSIG 10.0 10.0 10.0 A&B TLE Exit T, PSIG 9.0 9.0 9.0Cracked Gas Product wt % wt % wt % Hydrogen 1.26 1.39 1.29 Methane 18.8318.89 17.15 Ethane 4.57 4.54 4.38 Ethylene 31.25 31.11 28.94 Acetylene0.04 0.04 0.04 Propane 20.13 21.25 24.15 Propylene 17.60 17.88 18.36MAPD 0.26 0.25 0.25 Butanes 0.11 0.12 0.15 Butadiene 1.73 1.67 1.65Butenes + CPD 1.41 1.41 1.62 Other C5s 0.42 0.37 0.40 C6s+ 1.34 0.931.55 CO2 0.046 0.022 0.007 CO 1.001 0.134 0.061 Aver. M.W. 24.5 24.225.1

Example 59.2 at Fixed Total HC Flow, Steam/HC Ratio and Furnace FuelSupply (Conditions 1A, 1B, & 1C)

In order to check how the temperatures and crack gas composition changedwhen the total mass of hydrocarbons to the coil was held constant whilethe percent of r-pyoil 1052 a in the coil varied, steam flow to thetesting coil was held constant in AUTO mode, and the furnace was set tocontrol by a non-testing coil (Coil-C) outlet temp to allow the testingcoils to be in Float Mode. The r-pyoil 1052 a, in liquid form, withoutpreheating, was added into propane line at about 5, 10 and 15% byweight, respectively. When r-pyoil 1052 a flow was increased, propaneflow was decreased accordingly to maintain the same total mass flow ofhydrocarbon to the coil. Steam/HC ratio was maintained at 0.30 by aconstant steam flow.

Temperature Change: As the r-pyoil 1052 a content increased to 15%,crossover temperature dropped modestly by about 5° F., COT increasedgreatly by about 15° F., and TLE exit temperature just slightlyincreased by about 3° F., as shown in Table 19.

Cracked gas composition change: As r-pyoil 1052 a content in the feedincreased to 15%, methane, ethane, r-ethylene, r-butadiene and benzenein cracked gas all went up by about 0.5, 0.2, 2.0, 0.5, and 0.6percentage points, respectively. r-Ethylene/r-propylene ratio went up.Propane dropped significantly by about 3.0 percentage points, butr-propylene did not change much, as shown in Table 19A. These resultsshowed the propane conversion increased. The increased propaneconversion was due to the higher COT. When the total hydrocarbon feed tocoil, steam/HC ratio and furnace fuel supply are held constant, the COTshould go down when crossover temperature drops. However, what was seenin this test was opposite. The crossover temperature declined but COTwent up, as shown in Table 19a. This indicates that r-pyoil 1052 acracking does not need as much heat as propane cracking on the same massbasis.

TABLE 19A Variation of R-pyoil content and its effect on cracked gas andtemperatures (Steam/HC ratio and furnace firebox were held constant).1A, 1A, 1B, 1B, 1C, 1C, Base-line Base-line 5% Pyoil 5% Pyoil 10% Pyoil10% Pyoil 15% Pyoil 15% pyoil A&B Propane flow, klb/hr 11.87 11.86 11.2511.25 10.66 10.68 10.06 10.07 A&B Pyoil Flow, lb/hr 0 0 537 536 10741074 1776 1778 A&B Steam flow, lb/hr 3562 3556 3544 3543 3523 3523 35623560 A&B total HC flow, klb/hr 11.87 11.86 11.79 11.78 11.74 11.75 11.8411.85 Pyoil/(poil + propane), % 0.0 0.0 4.6 4.6 9.2 9.1 15.0 15.0Steam/HC, ratio 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 A&B Crossover T,F. 1092 1091 1092 1092 1090 1090 1088 1087 A&B COT, F. 1499 1499 15031503 1509 1509 1514 1514 A&B TLE Exit T, F. 691 691 692 692 692 692 693693 A&B TLE Inlet, PSIG 10.0 10.0 10.5 10.5 10.0 10.0 10.0 10.0 A&B TLEExit T, PSIG 9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 Cracked Gas Product wt % wt% wt % wt % wt % wt % wt % wt % Hydrogen 1.26 1.39 1.40 1.32 1.33 1.281.31 1.18 Methane 18.83 18.89 18.96 18.74 19.31 19.08 19.61 19.16 Ethane4.57 4.54 4.59 4.69 4.70 4.81 4.67 4.85 Ethylene 31.25 31.11 31.52 31.6232.50 32.63 33.06 33.15 Acetylene 0.04 0.04 0.04 0.04 0.05 0.05 0.050.05 Propane 20.13 21.25 20.00 19.95 18.58 18.65 16.97 17.54 Propylene17.60 17.88 17.85 17.86 17.79 17.85 17.58 17.81 MAPD 0.26 0.25 0.27 0.270.29 0.29 0.30 0.30 Butanes 0.11 0.12 0.11 0.11 0.10 0.10 0.10 0.10Butadiene 1.73 1.67 1.86 1.86 2.04 2.03 2.23 2.17 Butenes + CPD 1.411.41 1.52 1.52 1.59 1.57 1.67 1.65 Other C5s 0.42 0.37 0.38 0.38 0.380.37 0.40 0.39 C6s+ 1.34 0.93 1.37 1.50 1.24 1.21 1.95 1.56 CO2 0.0460.022 0.012 0.016 0.011 0.011 0.007 0.008 CO 1.001 0.134 0.107 0.1070.085 0.088 0.086 0.084 Aver. M.W. 24.5 24.2 24.2 24.4 24.2 24.4 24.224.6

Example 59.3 at Constant COT and Steam/HC Ratio (Conditions 2B, & 5B)

In the previous test and comparison, effect of r-pyoil 1052 a additionon cracked gas composition was influenced not only by r-pyoil 1052 acontent but also by the change of COT because when r-pyoil 1052 a wasadded, COT changed accordingly (it was set to Float Mode). In thiscomparison test, COT was held constant. The test conditions and crackedgas composition are listed in Table 19B. By comparing the data in Table19B, the same trend in cracked gas composition was found as in the caseExample 59.2. When r-pyoil 1052 a content in the hydrocarbon feed wasincreased, methane, ethane, r-ethylene, r-butadiene in cracked gas wentup, but propane dropped significantly while r-propylene did not changemuch.

TABLE 19B Changing r-Pyoil 1052a content in HC feed at constant coiloutlet temperature. 5B, Pyoil 2B, 15% 2B, 15% 5%@low T Pyoil Pyoil A&BPropane flow, klb/hr 11.85 10.07 10.07 A&B Pyoil Flow, lb/hr 601 17781777 A&B Steam flow, lb/hr 3738 3560 3559 A& B total HC flow, klb/hr12.45 11.85 11.85 Pyoil/(poil + propane), % 4.8 15.0 15.0 Steam/HC,ratio 0.30 0.30 0.30 A&B Crossover T, F 1062 1055 1059 A&B COT, F 14781479 1479 A&B TLE Exit T, F 697 688 688 A&B TLE Inlet, PSIG 10.0 10.010.0 A&B TLE Exit T, PSIG 9.0 9.0 9.0 Cracked Gas Product wt % wt % wt %Hydrogen 1.20 1.12 1.13 Methane 16.07 16.60 16.23 Ethane 4.28 4.81 4.65Ethylene 27.37 29.33 28.51 Acetylene 0.03 0.04 0.04 Propane 27.33 24.0125.51 Propylene 18.57 18.45 18.59 MAPD 0.23 0.27 0.25 Butanes 0.17 0.140.16 Butadiene 1.50 1.94 1.76 Butenes + CPD 1.63 1.65 1.73 Other C5s0.40 0.35 0.35 C6s+ 1.17 1.21 1.03 CO2 0.007 0.010 0.007 CO 0.047 0.0650.054 Aver. M.W. 25.8 25.7 25.9 C2H4/C3H6, wt/wt 1.47 1.59 1.53

Example 59.4 Effect of COT on Effluent Composition with R-Pyoil 1052 ain Feed (Conditions 1C, 2B, 2C, 5A & 5B)

r-Pyoil 1052 a in the hydrocarbon feed was held constant at 15% for 2B,and 2C. r-pyoil for 5A and 5B were reduced to 4.8%. The totalhydrocarbon mass flow and steam to HC ratio were both held constant.

On cracked gas composition. When COT increased from 1479° F. to 1514° F.(by 35° F.), r-ethylene and r-butadiene in the cracked gas went up byabout 4.0 and 0.4 percentage points, respectively, and r-propylene wentdown by about 0.8 percentage points, as shown in Table 20.

When r-pyoil 1052 a content in the hydrocarbon feed was reduced to 4.8%,the COT effect on the cracked gas composition followed the same trend asthat with 15% r-Pyoil 1052 a.

TABLE 20 Effect of COT on cracked gas composition. (Steam/HC ratio,R-pyoil 1052a content in the feed and total hydrocarbon mass flow wereall held constant) 5A, 1C, 1C, 2B, 2B, 2C, 2C, Add in 5B, 15% 15% 15%15% 15% 15% Pyoil 5% Pyoil Pyoil pyoil Pyoil Pyoil Pyoil Pyoil to C₃H₈5%@low T A&B Propane flow, klb/hr 10.06 10.07 10.07 10.07 10.07 10.0511.85 11.85 A&B Pyoil Flow, lb/hr 1775 1778 1778 1777 1777 1776 593 601A&B Steam flow, lb/hr 3552 3560 3560 3559 3560 3559 3737 3738 A&B totalHC flow, klb/hr 11.84 11.85 11.85 11.85 11.84 11.84 12.44 12.45Pyoil/(poil + propane), % 15.0 15.0 15.0 15.0 15.0 15.0 4.8 4.8Steam/HC, ratio 0.30 0.30 0.30 0.30 0.30 0.30 0.30 0.30 A&B Crossover T,F. 1088 1087 1055 1059 1075 1076 1081 1062 A&B COT, F. 1514 1514 14791479 1497 1497 1492 1478 A&B TLE Exit T, F. 693 693 688 688 690 691 698697 A&B TLE Inlet, PSIG 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 A&B TLEExit T, PSIG 9.0 9.0 9.0 9.0 9.0 9.0 9.0 9.0 Cracked Gas Product wt % wt% wt % wt % wt % wt % wt % wt % Hydrogen 1.31 1.18 1.12 1.13 1.25 1.251.29 1.20 Methane 19.61 19.16 16.60 16.23 18.06 17.87 17.15 16.07 Ethane4.67 4.85 4.81 4.65 4.72 4.75 4.38 4.28 Ethylene 33.06 33.15 29.33 28.5131.03 30.73 28.94 27.37 Acetylene 0.05 0.05 0.04 0.04 0.04 0.04 0.040.03 Propane 16.97 17.54 24.01 25.51 21.17 21.10 24.15 27.33 Propylene17.58 17.81 18.45 18.59 18.29 18.30 18.36 18.57 MAPD 0.30 0.30 0.27 0.250.27 0.28 0.25 0.23 Butanes 0.10 0.10 0.14 0.16 0.13 0.13 0.15 0.17Butadiene 2.23 2.17 1.94 1.76 1.87 1.99 1.65 1.50 Butenes + CPD 1.671.65 1.65 1.73 1.71 1.77 1.62 1.63 Other C5s 0.40 0.39 0.35 0.35 0.370.40 0.40 0.40 C6s+ 1.95 1.56 1.21 1.03 1.00 1.30 1.55 1.17 CO2 0.0070.008 0.010 0.007 0.009 0.009 0.007 0.007 CO 0.086 0.084 0.065 0.0540.070 0.072 0.061 0.047 Aver. M.W. 24.2 24.6 25.7 25.9 24.8 24.9 25.125.8

Example 59.5 Effect of Steam/HC Ratio (Conditions 4A & 4B)

Steam/HC ratio effect is listed in Table 21A. In this test, r-pyoil 1052a content in the feed was held constant at 15%. COT in the testing coilswas held constant in SET mode, while the COTs at non-testing coils wereallowed to float. Total hydrocarbon mass flow to each coil was heldconstant.

On temperature. When steam/HC ratio was increased from 0.3 to 0.5, thecrossover temperature dropped by about 17° F. since the total flow inthe coils in the convection section increased due to more dilutionsteam, even though the COT of the testing coil was held constant. Due tothe same reason, TLE exit temperature went up by about 13 F.

On cracked gas composition. In the cracked gas, methane and r-ethylenewere reduced by 1.6 and 1.4 percentage points, respectively, and propanewas increased by 3.7 percentage points. The increased propane in thecracked gas indicated propane conversion dropped. This was due to,firstly, a shorter residence time, since in the 4B condition, the totalmoles (including steam) going into the coils was about 1.3 times of thatin 2° C. condition (assuming the average molecular weight of r-pyoil1052 a was 160), and secondly, to the lower crossover temperature, whichwas the inlet temperature for the radiant coil, making the averagecracking temperature lower.

TABLE 21A Effect of steam/HC ratio. (r-Pyoil in the HC feed at 15%,total hydrocarbon mass flow and COT were held constant). 2C, 15% 2C, 15%4A, Stm 4B, Stm Pyoil Pyoil ratio 0.4 ratio 0.5 A&B Propane flow, 10.0710.06 10.08 10.08 klb/hr A&B Pyoil Flow, lb/hr 1777 1776 1778 1778 A&BSteam flow, lb/hr 3560 3559 4748 5933 A&B total HC flow, 11.84 11.8411.85 11.85 klb/hr Pyoil/(poil + propane), % 15.0 15.0 15.0 15.0Steam/HC, ratio 0.30 0.30 0.40 0.50 A&B Crossover T, F 1075 1076 10631058 A&B COT, F 1497 1497 1498 1498 A&B TLE Exit T, F 690 691 698 703A&B Feed Pres, PSIG 69.5 69.5 67.0 67.0 A&B TLE Inlet, PSIG 10.0 10.010.0 11.0 A&B TLE Exit T, PSIG 9.0 9.0 9.0 9.0 Cracked Gas Product wt %wt % wt % wt % Hydrogen 1.26 1.25 0.87 1.12 Methane 18.06 17.87 16.3016.18 Ethane 4.72 4.75 4.55 4.38 Ethylene 31.03 30.73 29.92 29.52Acetylene 0.04 0.04 0.05 0.05 Propane 21.17 21.10 23.40 24.88 Propylene18.29 18.30 18.67 18.49 MAPD 0.27 0.28 0.29 0.28 Butanes 0.13 0.13 0.150.16 Butadiene 1.87 1.99 2.01 1.85 Butenes + CPD 1.71 1.77 1.89 1.81Other C5s 0.37 0.40 0.43 0.37 C6s+ 1.00 1.30 1.38 0.84 CO2 0.009 0.0090.026 0.008 CO 0.070 0.072 0.070 0.061

On cracked gas composition. In the cracked gas, methane and r-ethylenewere reduced by 1.6 and 1.4 percentage points, respectively, and propanewas increased

Renormalized cracked gas composition. In order to see what the lighterproduct composition could be if ethane and propane in the cracked gaswould be recycled, the cracked gas composition in Table 21A wasrenormalized by taking off propane or ethane+propane, respectively. Theresulting composition is listed in Table 21B. It can be seen, olefin(r-ethylene+r-propylene) content went up with steam/HC ratio.

TABLE 21B Renormalized cracked gas composition. (R-pyoil in the HC feedat 15%, total hydrocarbon mass flow and COT were held constant). 2C, 15%4A, Stm 4B, Stm Pyoil ratio 0.4 ratio 0.5 A&B Propane, flow, 10.07 10.0810.08 klb/hr Pyoil/(poil + propane), % 15.0 15.0 15.0 Steam/HC, ratio0.30 0.40 0.50 A&B Crossover T, F 1075 1063 1058 A&B COT, F 1497 14981498 Renorm. w/o Propane wt % wt % wt % Hydrogen 1.60 1.14 1.49 Methane22.91 21.28 21.54 Ethane 5.99 5.94 5.83 Ethylene 39.36 39.06 39.29Acetylene 0.05 0.06 0.06 Propylene 23.21 24.37 24.62 MAPD 0.34 0.38 0.38Butanes 0.17 0.20 0.21 Butadiene 2.37 2.63 2.46 Butenes + CPD 2.16 2.472.41 Other C5s 0.46 0.56 0.50 C6s+ 1.27 1.80 1.12 CO2 0.011 0.033 0.010CO 0.089 0.091 0.081 C2H4 + C3H6 62.57 63.43 63.91 Renorm. w/o C2H6 +C3H8 wt % wt % wt % Hydrogen 1.70 1.21 1.58 Methane 24.37 22.62 22.87Ethylene 41.87 41.52 41.73 Acetylene 0.06 0.06 0.06 Propylene 24.6925.91 26.15 MAPD 0.36 0.40 0.40 Butanes 0.18 0.21 0.22 Butadiene 2.522.79 2.61 Butenes + CPD 2.30 2.62 2.55 Other C5s 0.49 0.60 0.53 C6s+1.35 1.91 1.19 CO2 0.012 0.035 0.011 CO 0.094 0.097 0.086 C2H4 + C3H666.55 67.43 67.87

Effect of total hydrocarbon feed flow (Conditions 2C & 3B) An increasein total hydrocarbon flow to the coil means a higher throughput but ashorter residence time, which reduces conversion. With r-pyoil 1052 a at15% in the HC feed, a 10% increase of the total HC feed brought about aslight increase in the propylene:ethylene ratio along with an increasein the concentration of propane without a change in ethane, when COT washeld constant. Other changes were seen on methane and r-ethylene. Eachdropped about 0.5 ˜0.8 percentage points. The results are listed inTable 22.

TABLE 22 Comparison of more feed to coil (Steam/HC ratio = 0.3, COT isheld constant at 1497F). 2C, 15% 2C, 15% 3B, 10% 3B, 10% Pyoil Pyoilmore FD more FD A&B Propane flow, 10.07 10.06 11.09 11.09 klb/hr A&BPyoil Flow, lb/hr 1777 1776 1956 1957 A&B Steam flow, lb/hr 3560 35593916 3916 A&B total HC flow, 11.84 11.84 13.04 13.05 klb/hrPyoil/(poil + propane), % 15.0 15.0 15.0 15.0 Steam/HC, ratio 0.30 0.300.30 0.30 A&B Crossover T, F 1075 1076 1066 1065 A&B COT, F 1497 14971497 1497 A&B TLE Exit T, F 690 691 698 699 A&B TLE Inlet, PSIG 10.010.0 10.3 10.3 A&B TLE Exit T, PSIG 9.0 9.0 9.0 9.0 Cracked Gas Productwt % wt % wt % wt % Hydrogen 1.26 1.25 1.19 1.24 Methane 18.06 17.8717.23 17.31 Ethane 4.72 4.75 4.76 4.79 Ethylene 31.03 30.73 30.02 29.95Acetylene 0.04 0.04 0.04 0.04 Propane 21.17 21.10 22.51 22.31 Propylene18.29 18.30 18.44 18.28 MAPD 0.27 0.28 0.28 0.28 Butanes 0.13 0.13 0.150.14 Butadiene 1.87 1.99 1.93 1.95 Butenes + CPD 1.71 1.77 1.82 1.82Other C5s 0.37 0.40 0.41 0.42 C6s+ 1.00 1.30 1.15 1.39 CO2 0.009 0.0090.009 0.008 CO 0.070 0.072 0.065 0.066

r-pyoil 1052 a is successfully co-cracked with propane in the same coilon a commercial scale furnace.

1-60. (canceled)
 61. A cracker feedstock composition comprising arecycle content pyrolysis oil composition (r-pyoil), wherein saidr-pyoil is present in said feedstock in an amount of not more than 20%by weight, based on the total weight of the feedstock.
 62. Thecomposition of claim 61, wherein at least 5 weight percent of saidr-pyoil is obtained from the pyrolysis of recycled waste.
 63. Thecomposition of claim 62, wherein not more than 95 weight percent of saidr-pyoil is obtained from the pyrolysis of recycled waste.
 64. Thecomposition of claim 63, wherein said recycled waste comprises wasteplastics, waste textiles, waste carpet fibers, waste modified cellulose,waste biomass, post-industrial waste streams, intermediate industrialwaste streams, or combinations thereof.
 65. The composition of claim 64,wherein at least a portion of said r-pyoil is obtained from thepyrolysis of waste plastic.
 66. The composition of claim 61, whereinsaid cracker feedstock has not been hydrotreated.
 67. The composition ofclaim 61, wherein said r-pyoil is present in said cracker feedstock inan amount of not more than 20weight percent and/or at least about 1weight percent.
 68. The composition of claim 67, wherein said crackerfeedstock composition comprises at least 60 weight percent and/or notmore than 100 weight percent of non-recycle C5 to C22 hydrocarbons. 69.The composition of claim 68, wherein said cracker feedstock has a finalboiling point of not more than 360° C. and/or at least 200, ° C.
 70. Thecomposition of claim 69, wherein not more than 25 weight percent of thecracker feedstock has a boiling point of 300° C. or more.
 71. Thecomposition of claim 70, wherein at least 0.5 weight percent of saidcracker feedstock has a boiling point of 300° C. or more.
 72. Thecomposition of claim 71, wherein said cracker feedstock has a total C15+content of not more than 25 weight percent, based on the total weight ofthe stream.
 73. The composition of claim 72, wherein said crackerfeedstock has a total C15+ content of at least 0.5 weight percent, basedon the total weight of the stream.
 74. The composition of claim 73,wherein said cracker feedstock has a total chlorine content of not morethan 20 ppm.
 75. The composition of claim 74, wherein said crackerfeedstock has a total chlorine content of at least 0.25 ppm.
 76. Thecomposition of claim 75, wherein said r-pyoil comprises not more thanabout 30 weight percent total aromatics, based on the total weight ofsaid r-pyoil.
 77. The composition of claim 76, wherein said r-pyoilcomprises at least 1 weight percent of total aromatics, based on thetotal weight of said r-pyoil.
 78. The composition of claim 77, whereinsaid r-pyoil comprises at least 15 weight percent and/or not more than80 weight percent of paraffins, based on the total weight of saidr-pyoil.
 79. The composition of claim 78, wherein said cracker feedstockcomprises not more than about 15 weight percent of oxygen-containinghydrocarbons.
 80. A method for making one or more olefins, comprising:(a) combining a recycle content pyrolysis oil composition (r-pyoil) witha non-recycle C5 to C22 hydrocarbon stream to form a cracker feedstream, wherein said r-pyoil is present in said cracker feed stream inan amount of not more than 20% by weight; and (b) cracking said crackerfeed stream in a cracker furnace to provide an olefin-containingeffluent stream.